Added <code> wrappers around 2 class names in the upgrade doc.

doc/xdocs/upgrade/upgrade-080-090.html

@@ -86,8 +86,8 @@ applications:
 	property equal to "username", as reflection is now used to retrieve the property displayed.<br><br></li>
 		
 	<li>
-	Users of net.sf.acegisecurity.wrapper.ContextHolderAwareRequestFilter should note that it has been
-	renamed to net.sf.acegisecurity.wrapper.SecurityContextHolderAwareRequestFilter.<br><br>
+	Users of <code>net.sf.acegisecurity.wrapper.ContextHolderAwareRequestFilter</code> should note that it has been
+	renamed to <code>net.sf.acegisecurity.wrapper.SecurityContextHolderAwareRequestFilter</code>.<br><br>
 	</li>
 		
 	<li>