manually bust cache

A number of people using recent sources experimenting with
caches will need to bust the cache at least once.  While we have
correct caching implemented now, the previous caching
implementation requires one busting in order to clear things
through.

static/index.html

@@ -44,6 +44,6 @@
         <script src='/bower_components/d3/d3.min.js'></script>
         <script src='/bower_components/jquery/dist/jquery.min.js'></script>
         <script src='/js/dropdown.js'></script>
-        <script src='/js/client.js'></script>
+        <script src='/js/client.js?a'></script>
     </body>
 </html>