Cut, copy and paste shortcuts are not working if you switch to in-browser menus.

[RaymondLim]

1. Switch to in-browser menus by making the following changes.
   • Locate _isHTMLMenu function in command/Menus.js and make it return true.
   • Locate $("body").addClass("in-browser"); in brackets.js and use it unconditionally. (ie. comment out if and else)
2. Relaunch Brackets and try out cut, copy and paste shortcuts.

Result: None of them works in any text field or editor window.

[pthiess]

Reviewed - @gruehle , low prio