[1/2] Base: Quick pulldown

This adds an option to toggle between left, right & centre.
left is the 30% from left, right is 30% from right &
centre is 40% in the middle.

Change-Id: I258421ff453b5525c7cfcd83ef36b452673072ef

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java

Conflicts:
	core/java/android/provider/Settings.java