[multi-sources-removal] Drop pyrorql and zmqrql sources After a few years experementing "true" multi-sources, we're now moving to "copy-based" source à la datafeed. As pyro and zmq sources have no more known customers and the related code is in the way of future refactoring of cubicweb's core, we decided to drop support for those sources without backward compatibility. If you're still using a zmqrql or pyrorql source and you want to upgrade, ask support to move it to datafeed using a pre-3.19 version first. Related to #2919300 (first step)

for eschema in schema.entities():
    if not (eschema.final or 'cw_source' in eschema.subjrels):
        add_relation_definition(eschema.type, 'cw_source', 'CWSource', ask_confirm=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()