Changes to Celestial Templates when making System Mods

[Rocket]

Based on the excellent work by Brian Thrain and tomservo we identified the rendering of orbit lines broke at large celestial counts, this was largely because they were not being culled. In builds with revision 2909 onward, there will be some new celestial template classes. For now, these only really impact how their orbitlines are culled, and coloring used to draw any UI.

Specifically, there are a new template class layout for static celestials:

• TerrestrialBody (rocky body)
  • PlanetaryBody (spherical body, planet or moon etc...)
    • AtmosphericBody (spherical body with atmosphere)
  • MinorBody (non-spherical body, such as a minor moon)
    • Asteroid
    • Comet

Some changes have also been made that will affect culling of orbit lines, this should now allow thousands of celestial bodies.