SystemUI: Add double tap to sleep gesture

Change-Id: I4c54718e8ec8774677d13917b3a7ffa3b4b18cb5

Conflicts:
	core/res/res/values/config.xml
	packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBarView.java
Don't read configs on every touch event for double tap to sleep

Got the idea from Dave Kessler - VanirAOSP

Change-Id: Ice60896dbd0bcd2de1dbff07baa7bf60af0cad58
[1/2] Make double tap gesture configurable

Change-Id: I09c8530fc5d0b31013508ad04490756f3ce55c50