Raised by a resource when faced with a strange request method.
RFC 2616 (HTTP 1.1) gives us two choices when faced with this situation: If the type of request is known to us, but not allowed for the requested resource, respond with NOT_ALLOWED. Otherwise, if the request is something we don't know how to deal with in any case, respond with NOT_IMPLEMENTED.
When this exception is raised by a Resource's render method, the server will make the appropriate response.
This exception's first argument MUST be a sequence of the methods the resource *does* support.