ShipmentIn allows to make any inventory move
Lets say there is a Supplier Shipment with 1 Product, 1xUnit.
2. Update inventory moves, set quantity = 10 on inventory move
Result is that there is a move Supplier -> Storage 1 Unit, Storage -> Location -> 10 Unit. Quantity(Storage) == -9
Tryton shoudn't allow such inventory move to happen (assign first?)