Add Rotation settings, (1/2):

Thanks to CyanogenMod

Included:

- Rotation settings screen
  (Settings -> Display)
- Auto-rotate screen
  (Settings -> Display -> Rotation)
- Rotate lock screen
  (Settings -> Display -> Rotation)
- Rotation modes, (0-, 90-, 180-, 270 degrees)
  (Settings -> Display -> Rotation)
- Swap volume buttons when screen is rotated
  (Settings -> Display -> Rotation)