Purchase Requisition Auto RFQ / Bid Selection bridge

Compatibility module for purchase_requisition_auto_rfq and purchase_requisition_bid_selection.

Specifically, purchase_requisition_auto_rfq allows to create automatically RFQs for a tender, purchase_requisition_bid_selection distinguishes between bids and rfqs. This bridge module takes care that automatically generated documents are either bids of RFQs depending on the mode of the tender.