rails/rails — pull request #16526 by josevalim (2014-08-16 20:29:32+00:00)
Title: Move respond_with to the responders gem

respond_with (and consequently the class-level respond_to)
are being removed from Rails. Instead of moving it to a 3rd
library, the functionality will be moved to responders gem
(at github.com/plataformatec/responders) which already provides
some responders extensions.