[IMP] doc: document the api.model decorator
[IMP] doc: document the api.model decorator

X-original-commit: efa3a148cb178693b73af054cd6e19870d068454
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo