* _enforce_strict_type_hierarchy prevents creation of new records when top-level types are disabled

The * _enforce_strict_type_hierarchy option, whether set to strict or permissive, will prevent the creation of new records when top-level types are disabled. In some setups top-level types are employed as un-selectable guide terms, grouping sub-terms.

In cases where top-level terms are disabled, the first enabled subtype should be used as the root of the type hierarchy for purposes of applying strict type hierarchy restrictions.