Implemented ship motion controls.

TODO:

Clean up and encapsulate.
Implement ship explosion
Implement hyperdrive
Implement projectiles
Implement trail.
Implement asteroids
Implement asteroid explosion and fragmentation
Implement asteroids + ship
Implement enemy ships
Implement all elements
Implement projectiles
Implement collision detection



Signed-off-by: us3r <us3r@localhost.localdomain>