title: Specify supported media types when sending "415 unsupported media type"
body: <p>If a clients sends data in an unsupported media type to a HTTP server, the server answers with status "<a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.16" rel="noreferrer">415 unsupported media type</a>". But how to tell the client what media types are supported? Is there a standard or at least a recommended way to do so? Or would it just be written to the response body as text?</p>