Calculator: Digit grouping (and other things)

-Digit grouping (in settings, US Locale only)
-Lock graph page (in menu, on graph page)
-Disabled button state (for 2,3,4,5,6... in Binary)
-Functions enabled in matrices (ie: sin, cos)
-Delete/Clear in widget
-Widget saves to history

-Bugfix where decimals in matrices in languages with comas would fail

Change-Id: I24090c60f3b7b3a3427e6b2eb13dff20c3a83ceb