Update FullStory snippet (#480)

Link to new, CDN-hosted version.

lib/skate_web/templates/layout/_fullstory.html.eex

@@ -2,18 +2,22 @@
 <script>
 window['_fs_debug'] = false;
 window['_fs_host'] = 'fullstory.com';
+window['_fs_script'] = 'edge.fullstory.com/s/fs.js';
 window['_fs_org'] = 'AQKVD';
 window['_fs_namespace'] = 'FS';
 (function(m,n,e,t,l,o,g,y){
     if (e in m) {if(m.console && m.console.log) { m.console.log('FullStory namespace conflict. Please set window["_fs_namespace"].');} return;}
     g=m[e]=function(a,b,s){g.q?g.q.push([a,b,s]):g._api(a,b,s);};g.q=[];
-    o=n.createElement(t);o.async=1;o.crossOrigin='anonymous';o.src='https://'+_fs_host+'/s/fs.js';
+    o=n.createElement(t);o.async=1;o.crossOrigin='anonymous';o.src='https://'+_fs_script;
     y=n.getElementsByTagName(t)[0];y.parentNode.insertBefore(o,y);
     g.identify=function(i,v,s){g(l,{uid:i},s);if(v)g(l,v,s)};g.setUserVars=function(v,s){g(l,v,s)};g.event=function(i,v,s){g('event',{n:i,p:v},s)};
     g.shutdown=function(){g("rec",!1)};g.restart=function(){g("rec",!0)};
+    g.log = function(a,b){g("log",[a,b])};
     g.consent=function(a){g("consent",!arguments.length||a)};
     g.identifyAccount=function(i,v){o='account';v=v||{};v.acctId=i;g(o,v)};
     g.clearUserCookie=function(){};
+    g._w={};y='XMLHttpRequest';g._w[y]=m[y];y='fetch';g._w[y]=m[y];
+    if(m[y])m[y]=function(){return g._w[y].apply(this,arguments)};
 })(window,document,window['_fs_namespace'],'script','user');
 
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