function CombinedStream() {
  this.writable = false;
  this.readable = true;
  this.dataSize = 0;
  this.maxDataSize = 2 * 1024 * 1024;
  this.pauseStreams = true;

  this._released = false;
  this._streams = [];
  this._currentStream = null;
}
Move cursor up by `x`
@param  {Readline} rl - Readline instance
@param  {Number}   x  - How far to go up (default to 1)