code: function Response(statusCode, headers, body) {
    this.statusCode = statusCode;
    this.headers = {};
    for (var key in headers) {
      this.headers[key.toLowerCase()] = headers[key];
    }
    this.body = body;
  }
docs: A response from a web request
  
  @param {Number} statusCode
  @param {Object} headers
  @param {Buffer} body