Selectmenu: adjusted default demo description

Author: fnagel

demos/selectmenu/default.html

@@ -95,7 +95,7 @@
 
 <div class="demo-description">
 <p>The Selectmenu widgets provides a styleable select element replacement. It will act as a proxy back to the original select element, controlling its state for form submission or serialization </p>
-<p>The datasource is a native select element or a simple JavaScript array, provided to the widget using the source-option.</p>
+<p>The datasource is a native select element. Supports optgroups.</p>
 </div><!-- End demo-description -->
 
 </body>