Forward port Status Bar interface

Patch Set 1: Signal / Clock / Battery / Notification Count
Patch Set 2: Updated commit message

Change-Id: Iecd4bb06b95b14888916331f5d36327f3206aeef

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/res/values/strings.xml
	packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryController.java