Settings: Slims ElectronBeam get some love (2/2)

Features:
- You can select different crt off animation modes if device overlay
does not disable it at all
- disabled
- always horizontal (stock behaviour)
- always vertical (screen collapse from left and right to the middle)
- orientation dependent (means portrait = horizontal animation,
landscape = vertical animation)
- some minor fixes/code style improvements to 4.3 implementation

Change-Id: I35fb277b8da823d50cc4db1eec32ea597fe973f2