Build 0.2.0

-Reworked Laser class into a Weapons class
-Added Rockets as a new weapon type
-Created proper spawning of asteroids of various sizes
-Asteroids do not spawn on top of each other
-Expanded safe zone of spawning
-Added a level skip button for debugging purposes (will be removed on
release)
-Game ends after level 5
-Various code cleanup

Controls:
W - Forward
A - Turn Left
D - Turn Right
R - Rocket
SPACE - Laser
V - Level Skip