improve swipe between pull down animation

this greatly improves both animation and function of swipe between screens
it allows for a hold on the animation and also freezes the notification panel
to do: add fling animation so it keeps spinning?

Change-Id: I04c4332d6f3678eb331f52d90e0db4c3fe414454

Conflicts:

	packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java
white space and dupe entries??? WTF