title: deep extend (like jQuery's) for nodeJS
body: <p>I am struggling with deep copies of objects in nodeJS. my own extend is crap. underscore's extend is flat. there are rather simple extend variants here on stackexchange, but none are even close to jQuery.extend(true, {}, obj, obj, obj) ..
  (most are actually terrible and screw up the benefits of asnyc code.)</p>
  
  <p>hence, my question: is there a good deep copy for NodeJS? Has anybody ported jQuery's ?</p>