Create celestial body manager

[aggregate1166877]

[Parent issue: #74]

Details:
We need a way to dynamically load celestial bodies into the space scene. This manager needs to be aware of the mass, reflectivity, luminoscity etc of these bodies. It also needs parameters that allow manual data (so that we may produce systems from sources such as NASA). Any data will be accepted in JSON format (meaning NASA data would need ETL love first).

We need a mechanism to add load bodies into the scene once in range, and remove bodies from memory when far away. We need some sort of mechanism to replace far away bodies with sprites of little dots.

If it's an easy task, also add gravitational drag to warp drive when close to celestial bodies. If this turns out to be a lot of work, please create a new ticket instead.

Related: #7 #38 #46 #57 #58

[aggregate1166877]

Will name this the UniverseFactory.

[aggregate1166877]

Created a Bright Star Catalog converter as part of this task: BSC5P-JSON

[aggregate1166877]

Started process of making video-game-friendly star data here: Star-catalogs-for-video-games

[aggregate1166877]

Creating shader loader as part of this.

[aggregate1166877]

Seeing as the last 40 days has been been learning astronomy and processing star data, I thought I might create tickets in this project to reflect some of that work.

• Create process for converting NASA data to game data #58: Data transformation and preparation
• Implement realistic distant star glow #57: Make that data look good in-game