Lockscreen Notifications: dismiss all button, improve animations, cleanup

Conflicts:
	packages/Keyguard/src/com/android/keyguard/KeyguardViewManager.java
	packages/Keyguard/src/com/android/keyguard/NotificationHostView.java
	packages/SystemUI/res/layout/navigation_bar.xml
	packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardTouchDelegate.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java