When a platform is parked above a planet, the planet will be rendered in the background!

Now with rudimentary animations when arriving and departing from planet orbits.

Can be added to an existing save, though stationary platforms will need to be toggled off and on to update the render logic. (Automatic platforms will solve this themself)

Currently wip:
- Smoother planet animations, rather than the current linear movement and scaling.
- Config options for planet scale and position.
- Asteroid shadows show on top of planet render. I want to fix this, but may not be possible.
- (Also I'll get some better gallery photos soon)

Currently planets need to be manually added on my side to work with the mod. I'm working on a better solution, but for now just ask if you want a planet supported.
Currently supported mods:
- Realistic Celestial Universe
- Tenebris
- Terra Palus
- Maraxsis (Not out yet, but I added support just in case)
- Naufulglebunusilo
Mods that add duplicates of existing planets will likely not work currently. WIP actual modded planet support should fix this.

Known issues:
- Planets will not render if a platform arrives at an orbit while paused. Simply toggle pause on the platform to update it.
--- (This normally isn't something that happens, and I don't have a good fix for it using the current API, so this will likely not get fixed.)