OpenAtlas

At the moment, hierarchy and types cannot be deleted if entities or subtypes are connected. One reason for this is to prevent deleting accidentally a lot of type information. Nevertheless, there should be an option to do it because otherwise it could get very cumbersome to delete an obsolete hierarchy or type.
To ensure accidentally deletes, we should clearly warn that connections to entities will be deleted recursively.

Implementation
Now, when a type for deletion has subs and/or linked entities a warning page will be shown which also displays concerning subs and linked entities.