docs: function KeepAliveAgent(options)
  {
  	options = options || {};
  	http.Agent.call(this, options);
  
  	// Keys are host:port names, values are lists of sockets.
  	this.idleSockets = {};
  
  	// Replace the 'free' listener set up by the default node Agent above.
  	this.removeAllListeners('free');
  	this.on('free', KeepAliveAgent.prototype.freeHandler.bind(this));
  
  }