Publish the krtequals linter as a separate module

I'm hacking on a repository that uses KRT and I'd like to re-use the krtequals custom linter without having to copy over the source code. AFAIK the issue is that the krtequals linter is a nested module & there's no independent tagging so it cannot be externally fetched. Moving this code to it's own repository is very likely the easiest path forward