Moved keywords in language file

[snipe]

This just breaks out the invisible keywords that informs the admin settings search box, and adds barcodes to the list so folks can more easily find the barcodes settings since we merged those into labels.

[what-the-diff]

PR Summary

• Improvement in the Language File Organization
  The PR has made the language file cleaner by eliminating specific keywords related to various settings, like general settings, PHP overview and more. This removal helps in keeping the file concise and less cluttered.

• Introduction of a New 'keywords' Structure
  A much more orderly method is adopted to manage keywords associated with settings. A new 'keywords' array has been created in the language file to facilitate improved organization.

• Updates in Settings View
  The settings view has been updated to work with the newly introduced 'keywords' structure instead of using separate individual keyword strings, which have now been removed. This makes referencing easier and more efficient.

• Modification in Help Text for Label Settings
  There has been a slight adjustment in the help text provided for the label settings option. It now specifies "Barcodes & label settings" instead of just "Label sizes & settings." This provides a more comprehensive, clearer understanding for users.