Ruby 2.0 changed `respond_to?` to return false for protected methods.

Passing in true explicitly overrides this behavior.

http://tenderlovemaking.com/2012/09/07/protected-methods-and-ruby-2-0.html
Merge pull request #1 from abscondment/ruby2.0

Ruby 2.0 changed `respond_to?` to return false for protected methods.