Ceres, Eris, Ice, Rocks, and the Kuiper Belt

[ravenshining]

Content (Artwork)
Note: This is #192 but github was complaining about my use of the ∆ character so I renamed the branch, which apparently auto-closed the PR

Summary

Visit all three dwarf / historical planets! Eris is uninhabited, but Ceres boasts a tiny outfitter and a friendly cantina.

Mine for ice! It's worth less than silicon sure but it sure is pretty! On display now in the Kuiper Belt! The outfit description is quoting @Zitchas

Get confounded by useless rocks! They use the same sprite as the tileable ones and take forever to destroy, so you should catch on you're supposed to mine others. They share the same name as the tileable ones, too, so you can easily convert or copy some or all of a tiled system to having belts,

Also fixed Pluto's images.

Screenshots

Usage examples

Say your system has
asteroids "large metal" 1 1.5554

If you want to convert that to a belt, all you need do is define a belt, and then change the above line to:
minables "large metal" 1 1.5554

Although you'll want to multiply the values by 10 or 100 in order for them to show up and act similarly:
minables "large metal" 100 15.554

Testing Done

Shooting up, harvesting, and selling asteroids

Not Done But Can be Done in Another PR Later:

• Flesh out Eris and Ceres descriptions
• Use the ice and rocks elsewhere

Artwork Checklist

(If any artwork was added or changed by this PR, the following must be provided.)

• I updated the copyright attributions, or decline to claim copyright of any assets produced or modified.
• Include the '@2x' version of any added images alongside the regular image.
• Please upload a zipped file with the necessary image, blend, and texture assets to the main body of your pull request.
  ice 2x and xcf.zip

[TheGiraffe3]

Beautiful.

[Zitchas]

Given that water is one of the most important things for early space travel (source of water, oxygen, hydrogen, and thus all the core requirements to breath, drink, and produce energy!), it's a travesty it wasn't already a mineable resource.

I haven't been able to actually review this properly, just wanting to state that I approve of it in concept, and the pictures look good.