Add a variant script to check a whole channel for consistancy
Lots of changes, including specify multiple errata and repos on th ecommand line
multiple bug fixes after testing (previous version didn't work!)
rename channelconsistancycheck.py to repoconsistancycheck.py becuase it works on repodata directory/files without needing satellite
rewrite to allow for multiple packages with the same name in the repo(s)