title: How to enable multiple row selection by mouse in gtk.glade treeview?
body: <p>How to enable multiple row selection by mouse  , I use :</p>
  
  <pre><code> selection.set_mode(gtk.SELECTION_MULTIPLE)
  </code></pre>
  
  <p>but the multiple row selection is enabled only by keyboard (shift + arrowup/down)</p>