Transform GitHub urls to repositories, PRs and Issues #11
Description
On GitHub, internal URLs to repositories, issues, PRs, etc strip out the https://github.com... parts of the urls and display a shortened link (e.g. #3).
It would be nice to have this functionality built into Dashboard Changelog as well, especially since the assumption in the core plugin is that we're tracking GitHub Releases.
Possibly related to this could be linking @ mentions to the appropriate GH profile.