Contextual action bar diff options

Added contextual action bar for long presses on any
 of the changed files cards to either open in the internal
 viewer or in the browser.
Added new 'view in browser' icon
Change internal diff viewer icon to old view in browser
 icon
Bump min-API level to 14 (ICS) - A method to provide data
 to the contextual action bar was added in ICS and none of
 our users run versions less than ICS.

Change-Id: If3f54c995608ee84f082e41e44a4c2ddacb6e021
Changed files CAB

DiffViewer: Support no non-binary files in change
Long click on changed files group header opens contextual
 action bar
Extract some string resources
Set the title of the CAB to match the selected file
Style the CAB to match the action bar

Change-Id: I4371f8ff379e5f776f54a2eb6f3845d3e3182376