Support for parsing CODEOWNERS files

Given the similarity in parsing rules for gitignore files & [CODEOWNERS](https://docs.github.com/en/github/creating-cloning-and-archiving-repositories/about-code-owners) files, it would be great if this library added support for parsing CODEOWNERS files as well. I am unable to find a Go implementation for parsing CODEOWNERS that follows the spec correctly, as does yours.