Add an undoing & redoing system to the editor

desktop_version/lang/ar/strings.xml

@@ -636,6 +636,8 @@
     <string english="Enemy Type Changed" translation="تغير نوع الأعداء" explanation="level editor, user changed enemy appearance for the room" max="38*3" max_local="38*3"/>
     <string english="Platform speed is now {speed}" translation="تغيرت سرعة المنصات إلى {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3" max_local="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3" max_local="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3" max_local="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3" max_local="38*3"/>
     <string english="Reloaded resources" translation="أعيد فتح ملفات الموارد" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3" max_local="38*3"/>
     <string english="ERROR: Invalid format" translation="خطأ: صيغة المكتوب غير مناسبة" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3" max_local="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="فتحت الغرفة: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3" max_local="38*3"/>

desktop_version/lang/ca/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="S’ha canviat el tipus d’enemic" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="La velocitat de les plataformes és ara {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="S’han recarregat els recursos" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERROR: Format invàlid" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="S’ha obert el mapa: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/cy/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Newidiodd Math y Gelyn" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Cyflymder llwyfan yw {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Adnoddau wedi&apos;u hail-lwytho" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="GWALL: Fformat annilys" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Map wedi&apos;i lwytho: {filename}.vvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/de/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Feindtyp geändert" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Plattformgeschwindigkeit ist jetzt {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Ressourcen neu geladen" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="FEHLER: ungültiges Format" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Karte geladen: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/en/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/eo/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Malamika tipo ŝanĝiĝis" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Platforma rapido nun estas {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Resursoj reŝargiĝis" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERARO: malĝusta formo" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Ŝargiĝis mapo: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/es/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Tipo de enemigo cambiado" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="La velocidad plataforma es {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Recursos recargados" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERROR: Formato no válido" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Mapa cargado: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/es_419/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Tipo de enemigo cambiado" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Velocidad de las plataformas: {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Recursos recargados" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERROR: Formato no válido" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Mapa cargado: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/es_AR/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Tipo de enemigo cambiado" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Velocidad de las plataformas: {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Recursos recargados" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERROR: Formato no válido" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Mapa cargado: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/fr/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Type d&apos;ennemis modifié" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Vitesse des plateformes réglée sur {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Recharger les ressources" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERREUR : format invalide" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Carte chargée : {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/ga/strings.xml

@@ -630,6 +630,8 @@ Déan cóip chúltaca, ar eagla na heagla." explanation="translation maintenance
     <string english="Enemy Type Changed" translation="Athraíodh Cineál Naimhde" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="Luas na n-ardán {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Athlódáladh acmhainní" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="EARRÁID: Formáid Neamhbhailí" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Mapa lódáilte: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/it/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="Tipo di nemico cambiato" explanation="level editor, user changed enemy appearance for the room" max="38*3"/>
     <string english="Platform speed is now {speed}" translation="La velocità piattaforma ora è {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3"/>
     <string english="Reloaded resources" translation="Risorse ricaricate" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3"/>
     <string english="ERROR: Invalid format" translation="ERRORE: Formato non valido" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="Mappa caricata: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3"/>

desktop_version/lang/ja/strings.xml

@@ -664,6 +664,8 @@ Steam Deckには対応していません。" explanation="" max="38*5" max_local
     <string english="Enemy Type Changed" translation="敵の種類を変更しました" explanation="level editor, user changed enemy appearance for the room" max="38*3" max_local="38*2"/>
     <string english="Platform speed is now {speed}" translation="プラットフォームの速度を {speed} に変更しました" explanation="level editor, user changed speed of platforms for the room" max="38*3" max_local="38*2"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3" max_local="38*2"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3" max_local="38*2"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3" max_local="38*2"/>
     <string english="Reloaded resources" translation="リソースを再読み込みしました" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3" max_local="38*2"/>
     <string english="ERROR: Invalid format" translation="エラー: 無効な記述形式" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3" max_local="38*2"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="{filename}.vvvvvv をロードしました" explanation="successfully loaded level file" max="38*3" max_local="38*2"/>

desktop_version/lang/ko/strings.xml

@@ -628,6 +628,8 @@
     <string english="Enemy Type Changed" translation="적 종류 변경됨" explanation="level editor, user changed enemy appearance for the room" max="38*3" max_local="30*3"/>
     <string english="Platform speed is now {speed}" translation="플랫폼 속도 현재 {speed}" explanation="level editor, user changed speed of platforms for the room" max="38*3" max_local="30*3"/>
     <string english="Enemy speed is now {speed}" translation="" explanation="level editor, user changed speed of enemies for the room" max="38*3" max_local="30*3"/>
+    <string english="ERROR: Nothing to undo" translation="" explanation="level editor, user tried to undo with nothing to undo" max="38*3" max_local="30*3"/>
+    <string english="ERROR: Nothing to redo" translation="" explanation="level editor, user tried to redo with nothing to redo" max="38*3" max_local="30*3"/>
     <string english="Reloaded resources" translation="자원 다시 불러오기" explanation="level editor, reloaded graphics assets/resources, music and sound effects" max="38*3" max_local="30*3"/>
     <string english="ERROR: Invalid format" translation="오류: 이용 불가능한 포맷" explanation="user was supposed to enter something like `12,12`, but entered `as@df`" max="38*3" max_local="30*3"/>
     <string english="Loaded map: {filename}.vvvvvv" translation="불러온 지도: {filename}.vvvvvv" explanation="successfully loaded level file" max="38*3" max_local="30*3"/>