title: Find current time in ET: EST or EDT, as appropriate
body: <p>I have an application which needs to use Eastern Time for a certain part of the calculation rather than the local time.  I suppose this could all be done manually (extract UTC time, decide whether daylight savings is in effect by a table lookup, then shift by 4 or 5 hours as appropriate) but I wondered if there was a built-in way of doing this.</p>
  
  <p>Also, weren't there changes to DST recently in the US?  (I need to follow US rules on daylight savings.)  I wonder if those were incorporated into JavaScript releases, if it follows the old rules, or if it never knew about them in the first place.</p>