Usability Improvements

[MOARdV]

Right now, it's just a "generate a random solar system" tool, with very little useful beyond that. Things that it could stand:

• Solar System Creation #6
• Naming - name the system, the star, and the planets (all optional).
• Editability - once there's a system, allow things to be edited, with updates applied. For instance, changing the diameter of a rocky planet changes its mass, so recompute all the derived values. Allow planets to be deleted.
• Synthesis of planets/moons - allow the user to add new planets to the system, even starting from a blank solar system (set the star, then add planets). Remember to add flags to keep track of whether a system has been edited, so the application using this library can provide feedback about it.
• Serialization/deserialization - of the essential values. Derived values that aren't editable don't need to be serialized.
• Better demo - Something that can do a crude illustration of the solar system + a UI to browse and edit values.