title: Open Layers 3: How to create listener for a modify interaction
body: <p>I have managed to set up a modify interaction.</p>
  
  <p>The docs for ol.interaction.Modify (<a href="http://ol3js.org/en/master/apidoc/ol.interaction.Modify.html" rel="noreferrer">http://ol3js.org/en/master/apidoc/ol.interaction.Modify.html</a>) don't metion a single event that is fired when a feature is modified.</p>
  
  <p>Unlike for instance for ol.interaction.Draw (<a href="http://ol3js.org/en/master/apidoc/ol.interaction.Draw.html" rel="noreferrer">http://ol3js.org/en/master/apidoc/ol.interaction.Draw.html</a>) which works nicely.</p>
  
  <p>I need to update the coordinates in the database when a feature has been modified.</p>
  
  <p>How can I set up a listener?</p>