Return: Smart Pulldown [1/2]

Adds the ability to directly open the QS panel when there are
no notifications present in the notification panel.
This commit combines the enhancement by HardCorePawn for detectin
notification types for the same.

Credits: kufikugel, HardCorePawn

PS 2-4 : Cleanup

Change-Id: I3c9b048f2616d2b8950930cc5bfac27c2364e826

Conflicts:

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