Include matchers only in relevent spec types. Updated require stucture.
Added Warp::Instrument to allow inspection of method calls on any instance of a class.
Added activerecord-nulldb-adapter to Gemfile.
Added a ActionMatchers::CreateMatcher to allow matching on record creation.
Removed ruby2.2.0-preview2 from .travis.yml.
Merge branch 'feature-matchers'