title: Bind expand click event in jstree
body: <p>In jsTree when I click the expand icon(+), I catch the "click.jstree" event and  get the message "expand clicked!", on the other hand when I click in a node I expect just the "node clicked!" message.. gets it first but then prompt "expand clicked!" msg too..</p>
  
  <pre><code>$('#tree_2').jstree({..})
  .bind('click.jstree', function (e, datap) {
      alert("expand icon! clicked");
  
  }).bind('select_node.jstree', function (e, datap) {
      alert("node clicked");
  });
  </code></pre>
  
  <p>As you guess when I click to node, both of these functions are trigged but I need one trigger for this event just 'select_node.jstree' or etc. </p>