Settings: Forward port Kill app longpress back

Based on http://review.cyanogenmod.org/#/c/27235
Original author: DaneshM

Change-Id: I6e8bfb4e7e4a35c321a01debf8fdb3a38120267b

Conflicts:
	res/values/cm_strings.xml
	src/com/android/settings/DevelopmentSettings.java