widgetset upgrade instructions link

svn changeset:10142/svn branch:6.2

WebContent/release-notes.html

@@ -89,6 +89,10 @@ widget sets and refresh your project in Eclipse. If you are upgrading from earli
 6.1.0, notice that Vaadin 6.1 uses GWT 1.7.0 (included in the installation package). See
 <a href="#upgrading">General Upgrade Notes</a> for more details on upgrading.</p>
 
+<h2>Widgetset upgrade notes</h2>
+
+See preliminary instructions from <a href="http://dev.vaadin.com/wiki/WidgetSetUpgrade">wiki</a>.
+
 <h2><a name="upgrading">General Upgrade Notes</a></h2>
 
 <p>When upgrading from an earlier version of the Vaadin library, you should always do the following:</p>