Colormatic

It's out! Yes, it's one month late for the 1.18.2 release, but in my defense, I do this on an almost pure interest-only basis :P. This release contains a few quality of life improvements, including

• Warning when blocks, biomes, or grid properties are provided for colormaps outside of colormaps/custom, as these properties are ignored for them.
• grid properties now allow string items, which expand to { "biomes": [<the value>], "width": 1, "column": <auto-incremented> }.