Removed dependency on Pillar; defaults now live in the state

Also wrapped the whole thing in an os_family conditional to avoid
running on non-RedHat systems.
Fixed osfinger keynames; removed Fedora keys (Fedora doesn't need EPEL)
Added fedoraproject.org mirror redirect URL
Fixed OS conditional to only apply to CentOS & RHEL
Updated README with list of available states & link to install docs