Sets Cubium as a moon of Vesta. Why? I dunno, it seemed like a good idea at the time.

Adapted from Moshine Orbits Vulcanus. By which I mean I copied it and changed only the planet names and dependencies, which is about the extent of my competency.

If using Better Planets it is recommended to disable changing of Cubium location or adapt it for it's new moon status. Specifically, if still adjusting location with Better Planets use a much smaller distance as it will be in relation to Vesta rather than the sun.

I just discovered Better Asteroid Belt has an option for this. It's very likely that's what put the idea in my head. Still keeping this, though, as I don't currently use Better Asteroid Belt but want this option.