Allow ui.xml to include additional xml files to read

Use common portrait and landscape xml files based on resolution
defined by the device.

Change-Id: Iec528f9d846d49857ff98de1ac201e25dbb60339

Conflicts:
	gui/devices/320x480/res/ui.xml
	gui/devices/480x854/res/ui.xml
	gui/devices/540x960/res/ui.xml