Removes deprecation warnings

  # Link to discussion: https://github.com/rspec/rspec-expectations/issues/231
  # Link to changelog: https://github.com/rspec/rspec-expectations/blob/master/Changelog.md#2140rc1--2013-05-27
Moves specs to rspec new expectation syntax
Stop testing on Rubinius 1
Merge pull request #95 from brunohenrique/master

Little improvements
Bump rspec to version 3