Settings: Add heads up blacklist options. (2/2)

Change-Id: I13d849b49bee6f516b591625c2ea2e69dff12885

Conflicts:
	AndroidManifest.xml
	res/values/cm_strings.xml
	res/xml/heads_up_settings.xml
	res/xml/notification_drawer.xml
	src/com/android/settings/cyanogenmod/NotificationDrawer.java
	src/com/android/settings/headsup/HeadsUpSettings.java
Changed position for SystemSettingSwitchPreference