Merge branch 'firingFeature' into coreTests

Conflicts:
	Bullet-Inferno/src/se/dat255/bulletinferno/model/PlayerShipImpl.java
Added tests for GameImpl and PlayerShipImpl.
Added comments to the assert statements.
Merge branch 'development' into coreTests

Conflicts:
	Bullet-Inferno/src/se/dat255/bulletinferno/model/PlayerShipImpl.java
Starting to update tests to use the new Timer interface.
Slightly changed projectile drawing to appear more in center of ship.
Added basic physics simulation subsystem. No integration.
Removed legacy PhysicsSimulation, with impl.
Added physics shape factory that creates physics shapes, for now just rectangles...
Code clean-up: reversed parameter order for physics body def constructor.
Removed old code from MyGame (test).
Added physics to Game/Impl and basic simulation of bullet velocities.
Fixed method name in Timer
Implemented mouseMoved for desktop
Added docs folder, containing UML diagram over system interfaces.
Changed projectile speed and set Projectile to be a bullet in physics engine.
Cleanup
Fixed merge conflicts?
Merging Development to coreTests
Added gdx to test classpath