[#17] updated rainbow to 2.0 and the new api
removed Gemfile.lock from repo

apps should have Gemfile.lock checked in, to make sure everyone is
working with the same versions, but gems/libs shouldn't, since they will
be used in various environments anyway.

see also:
http://yehudakatz.com/2010/12/16/clarifying-the-roles-of-the-gemspec-and-gemfile/
more loose json requirement
don't use latest fakefs, it causes some problems
spec fixes
version 0.3.2