Ships (in progress), Mouse aiming for debugging

Ships and Ship AI (in progress).
CircleRectangleCollision function has been changed to support rotated
rectangles.
Mouse Aiming for debugging (F3 to toggle).
Mouse buttons can now be used as the switch.
Moved from SFML.Net 2.1 to 2.0 (fixes bug where the game doesn't regain
focus on click).