QuietHours Tile (1/2)

Allows user to toggle state of quiet hours

Part 2 : http://review.cyanogenmod.org/#/c/31302/

Patchset 2 : New drawables courtesy of Björn Lundén
         3 : Make multiuser compatible

Change-Id: I10f7b7befbf7405e47247d90bfee0f30c3ecd7c9

Conflicts:
	packages/SystemUI/res/values/strings.xml