Settings: customizable slim lockscreen background (2/2)

- color fill (with transparency slider)
- custom image  (with transparency slider)
- full transparent
- default

This Settingspart containes a small comment change for Notificationbackground settings

Patchset 2: cleanup

Change-Id: I6542dd72b02a9fcdbf1159fa95ba64fcfc75796e
Signed-off-by: Kristofer Ard <kristoferard@gmail.com>

Conflicts:
	res/values/cmx_arrays.xml
	res/values/cmx_strings.xml
	src/com/android/settings/cyanogenmod/LockscreenInterface.java