Long press back to kill configurable timeout (1/2)

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

Change-Id: Icb92ab96f5c0ebdb2b11ebdc02fcfc5b034f2637

Conflicts:
	res/values/custom_arrays.xml
	res/values/custom_strings.xml