rails/activeresource — pull request #145 by beautifulcode (2014-09-30 22:53:36+00:00)
Title: ActiveResource::Base#exists? now returns true for 200..206 response codes

Encountered this issue when my API returned a 204 for the HEAD request ActiveResource::Base#exists? sends.
This PR adds support for the other 2xx response codes which should all indicate that the record does in fact exist.