set data as URL string so At.js will launch Ajax request to the serve…

…r to get the JSON data

app/assets/javascripts/atWhoAutoComplete.js

@@ -1,17 +1,11 @@
 (function() {
 
   // settings at https://github.com/ichord/At.js/wiki/Base-Document#settings
-  const users = [];
-
-  (function getRecentlyActiveUsers() {
-    $.getJSON("/users/active", function(data) {
-      data.forEach(function(i) { users.push(i.user.username)})
-    });
-  })();
 
   var at_config = {
     at: "@",
-    data: users,
+    displayTpl: (item) => `<li>${item.username ? item.username : item.name}</li>`,
+    data: '/users/active',
     delay: 400,
     callbacks: {
       remoteFilter: debounce(function(query, callback) {