Add advanced power menu, (1/2):

Thanks to SlimRoms.

Included:
- Up to 8 buttons
- Button arrangement
- Custom icons:
  - Standard icons
  - System icons
  - individual icons, (choose icons from gallery)
- Icon color
- Icon color mode:
  - All icons
  - System icons
  - System and individual icons
  - Deactivated
- Text color

- Available buttons:
  - (Advanced) Reboot
  - Power off
  - Expanded desktop
  - Airplane mode
  - Screenshot
  - Screen record
  - Sound mode
  - Individual shortcuts