Settings: Make it clearer how SMS Limiting works and add 500 messages option

Change-Id: Ia7458d7e7cde1cfbb6641d4b05fd9caf59d21db8
QuietHours Tile (2/2)

Allows user to toggle state of quiet hours

Change-Id: I9d3234b993d250a7d43683b51c1c3254aaec262f

Conflicts:

	AndroidManifest.xml
	src/com/android/settings/Settings.java
	src/com/android/settings/cyanogenmod/QuickSettingsUtil.java

Conflicts:

	src/com/android/settings/Settings.java