Add System menu and PowerWidget configuration support from mr0/10.0

Change-Id: I4c34812be0bc39dbe93e21a29682717ccf9c077f

Conflicts:

	AndroidManifest.xml
	res/values/arrays.xml
	res/values/dimens.xml
	res/values/strings.xml
	res/xml/settings_headers.xml

Power_Widget test