New version of Numitras

[codester]

I've continued development of my trajectory analysis software: http://codester.bplaced.net/index.php?slab=numitras

Major improvements are:

- Three dimensions
- Advanced maneuvers
- Increased speed and precision (A simulated flight from Earth to Moon and back takes ~2 sec. to calculate)
- Plugin system

Please try the new version with Orbiter and tell me about any problems.