peek/peek — pull request #65 by nwjsmith (2014-12-09 19:13:27+00:00)
Title: Remove responders

Responders are [deprecated in Rails 4][1] so we remove the class-level
call to `respond_to`.

[1]: http://edgeguides.rubyonrails.org/4_2_release_notes.html#respond-with-class-level-respond-to