Add noscript tag for analytics.

index.html

@@ -14,6 +14,7 @@
     <link type="text/css" rel="stylesheet" media="screen" href="css/theme.css" />
     <link type="text/css" rel="stylesheet" media="screen" href="css/converse.min.css" />
     <script type="text/javascript" src="analytics.js"></script>
+    <noscript><p><img src="//stats.opkode.com/piwik.php?idsite=1" style="border:0;" alt="" /></p></noscript>
     <!-- Only for development: <script data-main="main" src="components/requirejs/require.js"></script> -->
     <![if gte IE 9]>
         <script src="builds/converse.website.min.js"></script>