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

settings: add scale down crt animation - thanks a ton to xploidwild

original author: kufikugel

PS2: Moved membar and density out of display to interface
PS3: rebase for readdition of garbage from CM

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: Iad5f07f1f01ed872dc09dfe7462f4cd6b428160d