Update readme.md

README.md

@@ -13,6 +13,8 @@ $( document ).ready(function() {
 
 index.html
 ```
-<div class="doodle" data-json="path/to/data.json"></div>
+<div class="doodle" data-json="path/to/data.json">
+    <input type="hidden" id="inputVal" value="{}">
+</div>
 
 ```
\ No newline at end of file