Quiet Hours: allow disabling of system sounds (1 of 2)

* this include touch and lockscreen sounds

Change-Id: I4b16be00ae24dafd0039834bf63f6df3ef918619
QuietHours: clean up and consolidate code

Change-Id: Ib745ba91f800489518f1c7b5d2512ba946039696
Merge "Quiet Hours: allow disabling of system sounds (1 of 2)" into cm-10.2
Merge "QuietHours: clean up and consolidate code" into cm-10.2