支持自动编号类型字段，第一步实现流水号
Created by: hotlong
参考：https://github.com/steedos/creator/issues/98 odoo 自动编号： https://github.com/odoo/odoo/blob/12.0/odoo/addons/base/models/ir_sequence.py
Created by: hotlong
参考：https://github.com/steedos/creator/issues/98 odoo 自动编号： https://github.com/odoo/odoo/blob/12.0/odoo/addons/base/models/ir_sequence.py