[server] move security/integrity hook management away from InternalSession.__init__
and to Repository.internal_{session,cnx} instead. Lets internal_cnx avoid
deprecation warnings.
for table, column in [
('transactions', 'tx_time'),
('tx_entity_actions', 'tx_uuid'),
('tx_relation_actions', 'tx_uuid')]:
repo.system_source.create_index(session, table, column)
commit()