Merge pull request #800 from bolt/bobdenotter-patch-1

Make sure Content factory has an (empty) fields

src/Configuration/Content/ContentType.php

@@ -39,6 +39,7 @@ class ContentType extends DeepCollection
             'singular_slug' => $name,
             'singular_name' => $name,
             'locales' => [],
+            'fields' => new Collection(),
         ]);
     }