From https://casablanca.codeplex.com/discussions/548792
Attempting to use ```.extract_json()``` on a request with a MIME type of ```application/x-json``` will fail with an error. While this is not the standard MIME type for JSON, it is common.
Attempting to use ```.extract_json()``` on a request with a MIME type of ```application/x-json``` will fail with an error. While this is not the standard MIME type for JSON, it is common.
