i18n for settings and shortcuts menus

[nardog]

Description of changes:
The settings menu (Ctrl+,) and "Keyboard Shortcuts" (Ctrl+Alt+H) are now translatable. The properties of optionGroups are now arrays instead of objects keyed by English labels. The string keys were generated by internal names prefixed by options. and converting camel case to hyphenated.

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Pull Request Checklist:

• No backwards incompatible changes were made to Ace's public interface which is defined through the main typings file (ace.d.ts) and its references:
  • https://github.com/ajaxorg/ace/blob/master/ace.d.ts
  • https://github.com/ajaxorg/ace/blob/master/ace-modes.d.ts
  • https://github.com/ajaxorg/ace/blob/master/ace-extensions.d.ts