Use svg favicon with ico fallback (#191)

Author: milesfrain

client/public/img/favicon-black.ico

@@ -6,9 +6,8 @@
   <meta content="utf-8" http-equiv="encoding">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
 
-  <link rel="icon" type="image/png" href="./img/favicon_clear-16.png" sizes="16x16">
-  <link rel="icon" type="image/png" href="./img/favicon_clear-32.png" sizes="32x32">
-  <link rel="icon" type="image/png" href="./img/favicon_clear-256.png" sizes="256x256">
+  <link rel="icon" type="image/svg+xml" href="/img/favicon-black.svg">
+  <link rel="alternate icon" href="/img/favicon-black.ico">
 
   <script type="text/javascript" src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
   <script type="text/javascript" src="//cdnjs.cloudflare.com/ajax/libs/jquery/1.12.4/jquery.js"></script>