code: function request(packet, json) {
    return _create(packet, 1, (METHODS[packet.method] || '') + packet.resource, json);
  }
docs: Serialize request to array or JSON.
  
  @param {Object}        packet
  @param {String}        packet.resource
  @param {String}        packet.id
  @param {*}             packet.body
  @param {Number|String} [packet.date]
  @param {Object}        [packet.headers]
  @param {String}        [packet.method] "get", "search", "post", "put", "delete", "sub", "unsub".
  @param {Boolean}       [json] true to generate JSON instead of array.
  @returns {Array|String|null}