Revert "Hide navbar option 1/2"

This reverts commit 5d9c9fd4de37082c329a090b222ea4c050dc8f44.

Conflicts:
	core/java/android/provider/Settings.java

Change-Id: I6d6ebdadfd1bf7d142980e6c5b9dcbca016f2d44
Revert "Revert "NavigationBar : Customization""

This reverts commit d36905ab18e73bb7fe6b86bf9ea937d08de61328.

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

Change-Id: I8610b09c7c061b7aed6d642e18e73d93e51e301d
Revert "Revert "Fix hardcoded "Cancel" string in Navbar editor""

This reverts commit 8b9b5094794b64a6f2a8ab04162c035715f9128e.
Revert "Revert "Navbar : Rework logic for determining orientation""

This reverts commit 9c724dcb92420dcd1b150938b2066922599f2b77.
Add back navbar

Change-Id: If6e331de4f7f9102473e02ca278ad63440df981e