Changes

quick-rma: create a fresh RMA next to a marketplace RMA that already authorizes a shipment line

Follow-up to 3e5766907. The fresh RMA for shipment 535011 was rejected
with 'Amount to be returned is greater than the amount shipped': the
Amazon RMA 30595 already authorizes both shipped HYDRO units, and
iDempiere's MRMALine.checkQty sums every completed/closed RMA line on a
shipment line (a completed RMA also takes no new lines).

quick-rma now collects the authorized qty per shipment line from CO/CL
RMAs and creates such an RMA line without M_InOutLine_ID (product + qty,
description notes the conflict); the receipt line still links to it via
M_RMALine_ID. useReturnedQty attributes receipt lines of unlinked RMA
lines to the shipment line by product (callers pass the shipment lines)
so the remaining qty stays correct.