Set invoice_lines when creating new outgoing moves
When an outgoing move is splitted into several inventory moves (for example because several lots are involved on the same move) tryton creates new moves to match the inventory structure. As the newly created move has the same origin as the previous one, I think it also makese sense to copy the inventory lines from it's template.
This allows to relate the invoice_line with all the created moves and not with only the original one.