[FIX] mrp: extra move should split move lots also and take into account procurement

When you produce or consume more than foreseen in a production order,
the system creates extra moves.  Before, in case of tracking, it did this without
transferring the stock.move.lots resulting in a wrong stock.  That is why now,
when we split moves, we also split the stock.move.lots

For the finished move, it is also important to split between the quantities
of the original procurement and what is extra as the extra might use a push rule e.g.