[mattermostGH-119] Add slash-command autocomplete functionality (matt…

…ermost#149)

* update mattermost-server dependency version

* set up slash-command autocomplete functionality

* update readme

* fix linting error

* run 'go mod tidy'

* fix minor bug

* re-register the command upon configuration change

README.md

@@ -11,10 +11,13 @@
 
 Start and join voice calls, video calls and use screen sharing with your team members via Zoom.
 
-Usage & Setup Guide
------
+## Usage & Setup Guide
+### Commands
+* **`/zoom start`** — Start a zoom meeting.
+* **`/zoom disconnect`** — Disconnect from zoom (if OAuth is enabled).
+* **`/zoom help`** — Display help message.
 
-Check our [GitBook](https://app.gitbook.com/@mattermost/s/plugin-zoom/) for all the documentation regarding to this plugin.
+Check our [GitBook](https://app.gitbook.com/@mattermost/s/plugin-zoom/) for further documentation about this plugin.
 
 ## Development
 

go.mod

@@ -4,7 +4,7 @@ go 1.12
 
 require (
 	github.com/dgrijalva/jwt-go v3.2.0+incompatible
-	github.com/mattermost/mattermost-server/v5 v5.23.1
+	github.com/mattermost/mattermost-server/v5 v5.25.1
 	github.com/mholt/archiver/v3 v3.3.0
 	github.com/pkg/errors v0.9.1
 	github.com/stretchr/testify v1.6.1