ERP5TypeInformation are used for Portal Types of Portal Types and needed to generate at
least Workflow Methods early at Zope startup (initializePortalTypeDynamicWorkflowMethods()
and portal_type_group_filter in the problem reported on MR 1032) for very basic Portal
Type classes (such as Category Tool). So, Leave these on the filesystem for now, we can
eventually deal with them later if necessary.