[server] make internal_cnx get and keep a connection to the db - internal_session worked that way - it's less surprising for users if their internal connections "just work", rather than having to deal with the cnxset when using low-level APIs Includes a backout of 3f62606c01a2 "[repo] Fix register_user" which is no longer needed. Depend on logilab-database 1.12.1 to avoid errors due to pointless check in python's sqlite3 binding.

sync_schema_props_perms('CWSourceHostConfig', syncperms=False)

sql('INSERT INTO cw_source_relation(eid_from, eid_to) '
    'SELECT e.eid,s.cw_eid FROM entities as e, cw_CWSource as s '
    'WHERE s.cw_name=e.source AND NOT EXISTS(SELECT 1 FROM cw_source_relation WHERE eid_from=e.eid AND eid_to=s.cw_eid)')
commit()