Merge pull request #86 from Sitefinity/draganov/demo-site-ribbon

Fixed demo ribbon html appended to scripts and styles

Author: nader-dab

Global.asax.cs

@@ -58,7 +58,7 @@ private void RequestEnd(RequestEndEvent @event)
             if (bool.Parse(SystemManager.CurrentHttpContext.Items[SystemManager.IsBackendRequestKey].ToString()))
                 return;
 
-            if (!response.ContentType.StartsWith("text/html"))
+            if (response.Headers["Content-Type"] == null || !response.Headers["Content-Type"].StartsWith("text/html"))
                 return;
 
             response.Write(watermarkHtml);