Revert "Settings: move keyguard wallpaper to system (2/2)"

This reverts commit 62de03db5f18054608ee923abf3f95936ae5d398.

Conflicts:
	src/com/android/settings/cyanogenmod/LockscreenInterface.java

Change-Id: Ia55485f73a65faaa3ada05d6d0adb531861d93a7