title: moment.js format for unix timestamp?
body: <p>I'm trying to convert a unix timestamp to local time using moment.tz .  I've noticed I have to use a format when passing in a date, like this</p>
  
  <pre><code>moment.tz(date, 'MM/DD/YYYY hh:mm a', zone).format('MM/DD/YYYY hh:mm a');
  </code></pre>
  
  <p>My problem is when I want to convert from a unix timestamp to calendar like date the conversion fails.  What should I pass for the format string?</p>
  
  <p>I've tried these two formats with no luck</p>
  
  <pre><code>var date = moment.tz(publishInterval.DateUnix, 'X', zone).format('MM/DD/YYYY hh:mm a');
  
  
  var date = moment.tz(publishInterval.DateUnix, zone).format('MM/DD/YYYY hh:mm a');
  </code></pre>