I would also like to commit some code standards to the repo (we still get folks occasionally submitting patches with 2-space or 1-tab indents). However this format seems sort of dead? I went to the repository for it and there's hardly any commits in the last five years.

Which repo did you go to? The specification repo has had several updates throughout the past year. Check out their other repositories too, the library and plugin repos seem well maintained. They even have a maven plugin which JRuby could use if all the source was already conformant.

Ok that is more promising. I just searched for "editorconfig" and eventually ended up at https://github.com/editorconfig/editorconfig.

@enebo I have no objections to including this. Even IntelliJ recognizes it.