Adding local file rendering support to Sample Container

javascript/samplecontainer/samplecontainer.js

 /**
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements. See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership. The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License. You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
@@ skipping 280 matching lines @@
         if (!data) {
           alert("Could not dump the current state.");
         }
         document.getElementById('gadgetState').innerHTML
           = gadgets.json.stringify(data);
       }
     );
   };
 
 })();