title: How to merge two dates in JavaScript?
body: <p>I have 2 date objects. I want to take the date from one and the time from the other and combine them into a new date object.</p>
  
  <pre><code>date.toString() = Wed Dec 21 2011 00:00:00 GMT+0000 (GMT)
  time.toString() = Sun Dec 31 2000 03:00:00 GMT+0000 (GMT)
  
  # I want to end up with
  datetime.toString() = Wed Dec 21 2011 03:00:00 GMT+0000 (GMT)
  </code></pre>
  
  <p>How can I best accomplish this?</p>