Allow OAuth1 callback to specify query string parameters

They are then parsed and provided to underlying HTTP package. We have to parse them so that signing of requests works properly. In addition, nonce used in the request is stored in the response so that user can verify JWT payloads returned from the server.
> Dictionary of request parameters to be encoded and placed in the URL (for GETs) or request body (for POSTs). If content or data is specified, params will always be placed in the URL.