bug: fix example

Author: jrconlin

js/index.html

@@ -72,7 +72,8 @@ <h1>VAPID verification</h1>
     Just make the values short so you don't run the risk of the server
     rejecting a request because the headers are too big.</p>
     <p>For example:
-    <code>{'ami_id':'e-1248296','cust_id':'a9afd519s919faio3'}</code></p>
+    <code>{'sub': '[email protected]', 'exp': 1470858133,
+           'ami_id':'e-1248296','cust_id':'a9afd519s919faio3'}</code></p>
     <div class="control">
     <button id="gen">Generate VAPID</button>
     </div>