Add a little text to the Delegation demo what the user should do

Author: Arian

demos/Element.Delegation/demo.html

@@ -1,6 +1,8 @@
 
 <input id="addDiv" type="button" value="Add a new div" />
 
+<p>Click one of the blocks:</p>
+
 <div id="container" >
 	<div class="item"></div>
 	<div class="item"></div>