Camera improvements

Added a choice of cameras.

Manual works the same as before. It follows the selected rocket. You can use the middle mouse button to drag the camera around. Zoom is manual.

Chase camera follows the rocket and faces the same direction as the rocket is. Zoom is manual.

Cinematic camera is completely new. It gives the best view that it can at all times. You can adjust the zoom manually. You can drag the camera away for a quick look but it will snap back into place.