added tree component demo link in the project demo

Author: jrencz

demo/index.html

@@ -23,8 +23,11 @@
     <div class="jumbotron">
         <h1>Tree filter</h1>
 
-        <p class="lead">Node filter for Tree - the AngularJS Tree component with drag and drop support.</p>
-
+        <p class="lead">
+            Node filter for Tree - the <a href="https://jimliu.github.io/angular-ui-tree/">AngularJS Tree component</a>
+            with drag and drop support.
+        </p>
+        
         <p><a class="btn btn-lg btn-success" href="https://github.com/ee/agnular-ui-tree-keyboard" role="button">
             Code on GitHub</a></p>
     </div>