prosha/README.md

This needs a title

Highest priority:

• Fix issue with curve_horn_* that prevents geometry being joined in middle.
• Consider trampolining to_mesh. My call stack seems needlessly deep in spots. Can I make tail-recursive?

Important:

• Grep for all TODOs in code, really.
• Look at everything in README.md in automata_scratch.
• Implement some of the tougher examples from the above too, e.g. the triple nested spiral
• Lots of Rust-kosher refactoring (once I understand Rust better)
• Actual Rust-style docs!

If I'm bored:

• Fix links in tri_mesh docs that use relative paths & do a PR?
• Look in https://www.nalgebra.org/quick_reference/# for "pour obtain". Can I fix this somehow? Looks like a French-ism that made its way in.