v2026.2

What's Changed

• Move to github actions, and modernise the dependencies (Python 3 baby!)
• Fix the kerning, add a character generation phase to the xkcd-script process
• Refine diacritics
• Add a new processing stage to inject glyphs from extra sources. Add a basic Eszett/ß glyph
• Correctly map the dash-like characters from the original handwriting
• Add the full greek alphabet, and Æ, Œ, æ, œ
• Add initial mathjax v3 support