code: function(token, callback) {
      return this._transport.httpRequest({
        method : 'POST',
        url : this.revokeServiceUrl,
        body: querystring.stringify({ token: token }),
        headers: {
          "Content-Type": "application/x-www-form-urlencoded"
        }
      }).then(function(response) {
        if (response.statusCode >= 400) {
          var res = querystring.parse(response.body);
          if (!res || !res.error) {
            res = { error: "ERROR_HTTP_"+response.statusCode, error_description: response.body };
          }
          var err = new Error(res.error_description);
          err.name = res.error;
          throw err;
        }
      }).thenCall(callback);
    }
docs: OAuth2 Revoke Session or API Token
  
  @param {String} token - Access or Refresh token to revoke. Passing in the Access token revokes the session. Passing in the Refresh token revokes API Access.
  @param {Callback.<undefined>} [callback] - Callback function
  @returns {Promise.<undefined>}