switch over to mithril fragment method

ui/app.js

@@ -20,13 +20,13 @@ export default class App {
     let db = WbDb.get();
 
     if (db.failed)
-      return m("[", [
+      return m.fragment([
         m("h1", "Watterblock kann nicht geöffnet werden"),
         m("p", "Die IndexedDB-Verbindung funktioniert gerade nicht"),
       ]);
 
     if (db.blocked)
-      return m("[", [
+      return m.fragment([
         m("h1", "Watterblock muss warten"),
         m("p",
           "Bitte schließe alle anderen Tabs, in denen der Watterblock " +

ui/game.js

@@ -8,7 +8,7 @@ export default class GameView {
   view({ attrs: { model } }) {
     let { ourPoints, theirPoints } = model.result;
 
-    return m("[", [
+    return m.fragment([
       (model.rounds.length !== 0)
         ? m("tbody", model.rounds.map(function(round) {
             return m("tr", [