2.9.1 Release

What's Changed

• Clean up unwanted files in cores before installing. by @LoneBoco in #77
• Fixed stupid bug in the version regex @mattpannella in #79

This really isn't a bugfix release, but there's an issue with the regex that pulls the semver out of the git release tag, and if i labeled this 2.10.0 it would never trigger a new update download. whatever, no one cares about the version