Merge remote-tracking branch 'github/cm-11.0' into cm-11.0

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/SignalClusterView.java
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java

Change-Id: Ib129dab2fa87c3c51e51be2285b98392d31215dd
Remove show_navigation setting

Change-Id: I28fc6703bfeb9cb16406e0f18f2c0249acae3967
Runtime toggle of navbar

This adds the framework support for enabling the Navigation bar
on devices with hardware keys. It is toggled from Settings, and
depends on device-specific support for the KeyDisabler hardware
control

Change-Id: I88fecb2ca1e8613591c327a93f53909b00239cd8 (reverted from commit b6a1eb3bd5438906f06a076a7c29d97376638496)