code: function onEnd() {
  		self.elapsed = process.hrtime( self.timer );
  		self.end = Date.now();
  		self.res.body = body;
  		delete cache[ self.rid ];
  		delete self.req.opts[ 'agent' ];
  		next();
  	}
docs: FUNCTION: onEnd()
  Callback invoked after a response ends.
  
  @private