Some fixes coming your way!

Some more fixes based on feedback we've received from players like you!
- Fixed issue where Asteroid base map units were flying
- Balanced dogecoin rewards from enemies to increase difficulty
- Fixed Next Level button on some maps to go to the correct next level
- Changed main menu to have vehicles
- Added light indicators to Fly Down and Asteroid Base to make it obvious to clueless players where walls should be placed
- Added more bugs to fix later