added error message when user tries to run tests without having the appropriate RubyMotion version available
updated to RubyMotion 2.33
Merge pull request #548 from clearsightstudio/update/rubymotion-availability-error

Added error message when user tries to run tests without having the appropriate RubyMotion version available.
Added Omniref badge
Updated badges
Merge branch 'master' into feature/warn-on-invalid-property
Extensive work on tests