screenshot: quick delete action

Add option to delete screenshot from notification

Change-Id: I0f153bc3c72b902163b4ae75e220ddb09e3fcb11

Conflicts:
	packages/SystemUI/res/values/cm_strings.xml
Show confirmation for deleted screenshot.

Change-Id: I4a36cf06bf252e5e15fe08fbd054dc64a0a507ae

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