FwBase: Transparent NavBar

Added a transparent mode to the NavigationBar

Change-Id: Ic72f8ea29c31a087b1a0f4672a57c91b39dfd017
Signed-off-by: STELIX <ssspinni@gmail.com>

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java