Spherical Texture Mapping for OpenSCAD

This is a rewrite of the thing "Texture Mapping OpenSCAD by deltaModulator" in Node.js.

I optimized some stuff and made the code much more readable, but other than that it does the exact same thing as the original thing but in JavaScript.

You will need Node itself from https://nodejs.org/en/ and the NPM module "jimp", install it with: `npm install -g jimp`.

The moon image is in the public domain created by NASA: https://svs.gsfc.nasa.gov/4720