do not assume a default ordering by primary keys on relations
do not assume a default ordering by primary keys on relations

so that it does not override default order_by which may have been defined in
the sqlalchemy mapper:
http://docs.sqlalchemy.org/en/rel_0_7/orm/mapper_config.html#sqlalchemy.orm.mapper

FormAlchemy/formalchemy,camptocamp/formalchemy,camptocamp/formalchemy,FormAlchemy/formalchemy,camptocamp/formalchemy,camptocamp/formalchemy,FormAlchemy/formalchemy,FormAlchemy/formalchemy