wip : Planetary Transit

Paragon Flight System, Planetary Transit:

- Implement 2 step transit system
- Transit automatically switches between transit drive 1 and 2 based on double gravity bubble
- Implement manual transit
- Modify autopilot to activate transit drive 1 when ship leaves gravity bubble instead of using a constant speed threshold to determine that
- Modify autopilot to use transit drive 1 during planetary travel between gravity bubble and double gravity bubble. Ship should stay within this space for the entire duration of the trip.
- Autopilot switches to transit drive 2 when leaving the double bubble

* Transit drive 1 and 2 have constant speed for now