craigkuhns/Backbone-API — pull request #1 by groovetrain (2014-09-18 18:25:43+00:00)
Title: Fix for detecting application/json payloads

Firefox wouldn't allow updates to items. They would POST ok, but PUTs
would always return a 404. Reason was chrome was sending the normal
"application/json", but Firefox was sending "application/json;
charset=UTF-8".

This commit looks for the PRESENCE of applicaiton/json in the request
content type instead of the entire content_type being application/json