Fixes some bugs and a feature added

- Added game_config.txt to project so that Pokemon Fire Red can use in-game saving (may help other games with other features too)
- Added an opacity setting for the landscape controller
- Allow GBC roms to be loaded properly (provided they are not in ZIP archives - that bit isn't done yet)
- Enabled Pause/Resume in GBC - the button is still invisible, though, it's at the top of the controller between the volume buttons in the centre.