Fix skip summary metrics regression since introducing flotr2

Ting

2014-04-16 d0751dc352ef06c067593f31f5423fce357f8f1f

 src/main/java/com/gitblit/wicket/ExternalImage.java

@@ -27,6 +27,7 @@
      super(id, new Model<String>(url));

   }



   @Override

   protected void onComponentTag(ComponentTag tag) {

      super.onComponentTag(tag);

      checkComponentTag(tag, "img");