overlay: squashed commit to bring OmniROM / MMS features
- remove CM Camera / Torch settings
- add description to BT tethering config value
- add OmniTorch overlays: https://github.com/omnirom/android_device_lge_gee-common/commit/1b50908122531bec3d07101507d74d9b4d670f65
- add custom button config for OmniGears: https://github.com/omnirom/android_device_lge_gee-common/commit/5c51361bc3ebf750765e2d69f385014721c4e8f0
- add MMS support