added docs for unselect using click

Author: yoavaa

index.html

@@ -67,7 +67,7 @@ <h1>Basic Usage <small>(Classic style, default configuration)</small></h1>
             </div>
             <div class="col-md-6">
                 <p>Classic style of the tree control, set using the class <code>tree-classic</code>.</p>
-                <p>Click on the folder icons to open and close the tree nodes. Click on the node label to select a node in the tree.</p>
+                <p>Click on the folder icons to open and close the tree nodes. Click on the node label to select a node in the tree. A Second click on the node label will unselect the node.</p>
                 <p>The tree data is set using the <code>tree-model</code> attribute, which accepts either a node object or an array of node objects.
                     A Node object is a regular javascript object which has a <code>children</code> array property (children is the defuault name,
                     it can be overridden using the tree options). </p>