Allow to join an open group

Also:

* Refactor interacting with a remote event so that you can interact with
  a remote group as well
* Add a setting for group admins to pick between an open and invite-only
  group
* Fix new groups without posts/todos/resources/events/conversations URL
  set
* Repair local groups that haven't got their
  posts/todos/resources/events/conversations URL set
* Add a scheduled job to refresh remote groups every hour
* Add a user setting to pick when to receive notifications when there's
  new members to approve (will be used when this feature is available)
* Fix pagination for members

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

js/src/i18n/langs.json

@@ -10,7 +10,7 @@
   "fi": "suomi",
   "fr": "Français",
   "gl": "Galego",
-  "hu": "Magyar nyelv",
+  "hu": "Magyar",
   "it": "Italiano",
   "ja": "日本語",
   "kn": "Kannada",