(re)distribute incoming products when delivered != ordered

[Cor-Jan]

When the delivered products are less, more or different from the products ordered, how to cope with that?

There are 4 scenarios:

1. too much
2. too little
3. not delivered
4. not ordered

[wvengen]

1. too much - redistribute over member orders' tolerance (optional), rest to stock (see Rest ins Lager  foodcoops/foodsoft#35)
2. too little - recompute member distribution
3. not delivered - set result to zero and recompute member distribution
4. not ordered - add product to order and enter amount delivered, all to stock

Some foodcoops may not want to use stock (yet), in that case "to stock" means either doing nothing (leaving a difference between ordered and member orders), or assigning rest to a special ordergroup belonging to the foodcoop.

[wvengen]

mostly implemented in fresh-flow (not: rest to stock)

[wvengen]

This is done in the receive screen. Closing the issue here. Pending is putting the remainder in stock, but that's out of scope for the current issue.