Refactor

WIP - #18

Refactors what used to be a bash-like ruby script into a gem that can be installed. Separates the configuration data (moduleroot/ and *.yml) into a different repository.

Still needs:
 - update README
 - add a hook command
 - read configuration options from a file in the CWD
 - better error checking
perhaps use the path variable instead of the constant in the error message?