Travis Ruby Version Bumps
Make Ruby 2.1.2 the default version
Merge pull request #116 from triAGENS/ruby-version-bumps

Travis Ruby Version Bumps
Faraday and Faraday Middleware Version Bump

* Faraday is now on version 0.9.0
* Faraday Middleware is now on version 0.9.1
Update Development Dependencies: Rake, Inch, Mutant, Guard