Ability to add secondary star maps

[FluidNatalie]

For 2.1, it would be good if Mods similar to Metal and Stars could add a second star map.
The exact details as to how the other star maps work would be up to interpretation but I do have some ideas, such as "Linked" space locations, perhaps to let players navigate between the starmaps they can travel to locations that show up on both maps, so to get to StarMap2, you go to Galaxy Edge on StarMap1 and then the space ship shows up as being on Galaxy Edge on StarMap2 as well.

I realise that this is a big request as it would change how things like, space locations, star map backgrounds, and GUI would work but it would be cool.