title: Call save() in model while using Propel Versionable
body: <p>I just switched an existing Model to be <code>Versionable</code>.</p>
  
  <p>After debugging quite a lot, I now realized that there are a quite a few cases that I use <code>$this-&gt;save()</code> in the model quite a few times and that this finally causing duplicate entries in the Version table. </p>
  
  <p>Is the only way to prevent this by removing the <code>-save()</code> methods out of the model (I tried it out, it works) or is there another, more simple way to prevent the internal loop during version-creation and its saving?</p>