Add entry to change lock wallpaper via themes

Change-Id: I79e7160629bc43d1f1ca993833ea2fc538550475
Fix a number of aapt warnings.

The remaining warnings have their origin in AOSP.

Change-Id: I070d3cc1f5e9d4fc2bf7e442e58fe2bdc100ed0e
Merge remote-tracking branch 'upstream/cm-11.0' into cm-11.0