To do list

1. Fix enemy movement (Jelle)
2. Fix object – object collision (Jelle)
3. Fix player – object collision (Jelle)
4. Create music player (Cornel)
5. Fix level cycle (Serhan)
6. Create 2 player mode (Cornel)
7. We need some excellent levels to play (at least 6 levels is needed)
8. Clean doFrame in Game.java (Cornel)
9. We need an actual Game Over screen (Serhan)
10. Highscore (Cornel)