[settings] long press back to kill configurable timeout (2/2)

1 - 2 seconds (default)
2 - 1,5 seconds
3 - 1 second
4 - 0,5 second

Forward ported from crDroid kk

(cherry picked from commit 3e40de2ec6cc94a55b2a2962f808b2de35bf50cd)

Conflicts:
	res/values/cr_arrays.xml
	res/values/cr_strings.xml