[2/2] Navigation bar dimensions

- Change height when in portrait
- Change width when in landscape
- Option to enable or disable nav bar

This is partially ported from SlimRoms
Thanks to @kufikugel

Change-Id: Icac45d5c74f1722c1d044c6651ea686e95beade4

Conflicts:
	res/values/cr_arrays.xml
	res/values/cr_strings.xml
	res/xml/system_ui_settings.xml
	src/com/android/settings/cyanogenmod/SystemUiSettings.java