title: How to re-save the entity as another row in Doctrine 2
body: <p>Let's say I have entity <code>$e</code>. Is there any generic way to store it as another row, which would have the same entity data but another primary key?</p>
  
  <p>Why I need this: I'm implementing some sort of <a href="http://en.wikipedia.org/wiki/Temporal_database">Temporal Database</a> schema and instead of updating the row I just need to create another one.</p>