Currently the project settings overview also contain the custom fields. In order to make it easier to understand it should have a separate tab.

**Acceptance criteria**

- Have a separate tab “Custom fields”
- No changes to permissions.
- Begin of the deletion If there are no custom fields defined show a message “There are no custom fields defined yet.”
-End of the deletion Remove headline
- Remove check all/uncheck all
- Make styling consistent to tab “Modules” Begin of the insertion
- <s>If there are no custom fields defined show a message “There are no custom fields defined yet.”</s>End of the insertion