Add System menu and PowerWidget configuration support from mr0/10.0

Change-Id: I4c34812be0bc39dbe93e21a29682717ccf9c077f

Conflicts:
	AndroidManifest.xml
	res/layout-finger/order_power_widget_button_list_item.xml
	res/values/arrays.xml
	res/values/dimens.xml
	res/values/strings.xml
	res/xml/settings_headers.xml
A few fixes.

Change-Id: I9d12081adc81a04212e27cae5f30fa0dc195d3e5