code: function StreamFormatter(loggerManager, options) {
          if (!(this instanceof StreamFormatter)) {
              return new StreamFormatter(loggerManager, options);
          }
  
          stream.Readable.call(this, options);
          this._buffer = [];
          this._pushable = false;
          this._ended = false;
          loggerManager.on("message", this._handleMessage.bind(this));
          loggerManager.on("end", function () { this._handleMessage("END"); }.bind(this));
      }
docs: StreamFormatter objects are Readable streams. They output a string represntation
  of the log events generated by the "logger" variable.
  
  The "options" argument is passed directly to the stream.Readable constructor.
  No configuration of the log format is supported at this time.