Incremental master sync - lots of tests to merge in

Big things that have happened so far on this branch:
* no more Gemfile.lock - apparently gems should never commit Gemfile.lock to source control - http://yehudakatz.com/2010/12/16/clarifying-the-roles-of-the-gemspec-and-gemfile/ 
* rake task to run tests and immediately open the coverage report - `rake coverage`
* many tests have had VCR removed in favor of WebMock'd HTTP request mocking
* API dev key being loaded and set on Cb config from .env file - support for the remaining VCR-based tests
* removed all of the tests asserting incorrect API URLs - they were providing no value and not testing our code, they were testing what it means to 404.

It's not quite ready yet, but I intend on wrapping it up and merging by the end of the day today. There are still a couple failing VCR-based tests, just wanted to get the pull request up early in case any discussion is desired. Feel free to comment away!