Revert "make nsdetails not do a db->get under _openRWLock"

This reverts commit e13b346274d42b0ebbdb6e37e94a34a84a89bf0c.
Revert "make NamespaceIndex::init not open a dictionary under _openRWLock"

This reverts commit bd5291cce6f49823d374817d9684943b12bb93f3.