Remove old solar system generation.
Add stars.
Space systems use stars.
Planets!
Disambiguate planets & planet systems.
Polar coordinates.
SPACESystem has closure.
Systems and planets/stars have names.
Extract barycentres into a protocol.
Dumb constructors begone.
Merge remote-tracking branch 'origin/physics' into orbits

Conflicts:
	Space/SPACEStellarBody.h
	Space/SPACEStellarBody.m
Spread planets out a bit.
Assign colours.
Planets can have textures.
Merge pull request #5 from MecoKing/orbits

Star system reorganization & gas giant texture