Static CMS v4 (#246)

- Static CMS v4
- switch from jsdelivr to unpkg due to performance issues
- custom themes
- preset view_group

Reviewed-on: #246

static/admin/config/collections/cantorfora.js

@@ -19,12 +19,6 @@ const CantorforaCollection = {
     frame: true,
     size: "half",
   },
-  view_groups: [
-    {
-      label: "Entwürfe",
-      field: "draft",
-    },
-  ],
   summary_fields: ["title", "draft", "description"],
   sortable_fields: {
     fields: ["index", "title"],