took ES module demo out

for #2476 since not working

Author: adumesny

demo/esmodule.html

@@ -13,7 +13,7 @@
   <h1>ES Module loading demo</h1>
   <div class="grid-stack"></div>
 
-  <!-- loading GS as an ES module instead of commonjs all.js. get CORS error though -->
+  <!-- loading GS as an ES module instead of commonjs all.js. doesn't work (see #2476) and get CORS error locally -->
   <script type="module">
     import { GridStack } from '../dist/gridstack.js';
 

demo/index.html

@@ -12,6 +12,7 @@ <h1>Demos</h1>
     <li><a href="anijs.html">AniJS</a></li>
     <li><a href="cell-height.html">Cell Height</a></li>
     <li><a href="column.html">Column</a></li>
+    <!-- <li><a href="esmodule.html">ES Module test</a></li> -->
     <li><a href="float.html">Float grid</a></li>
     <li><a href="knockout.html">Knockout.js</a></li>
     <li><a href="mobile.html">Mobile touch</a></li>
@@ -38,7 +39,6 @@ <h1>Demos</h1>
     <li><a href="web-comp.html">Web Component</a></li>
     <li><a href="web1.html">Website demo 1</a></li>
     <li><a href="web2.html">Website demo 2</a></li>
-    <li><a href="esmodule.html">ES Module test</a></li>
   </ul>
   <h1>Angular wrapper</h1>
   <p>We now ship an <a href="https://github.com/gridstack/gridstack.js/tree/master/angular/" target="_blank">Angular Component</a>