Refactor to get this repository into stackforge

While this repository was originally factored to work with the Opscode
Chef repos for OpenStack, the community has since moved to Stackforge.
Therefore, bring this repository forward such that it supports the
model being used by those repositories. Changes include: adding tests
(more needed), renaming database.rb to db.rb to match style of
stackforge repos, add more README docs, licenses, Gemfiles and a
Berkshelf file.