HALO new vertical gestures (NOT READY FOR RELEASE)

itroduces step gestures

-- Clear all notifications
-- Clear current notification

(*)

-- Hide HALO
-- Silence HALO until woken

Change-Id: I4b5bb7ec612dc0eb1d95e970348b15fba1d79df0

Conflicts:
	packages/SystemUI/res/values/strings.xml