Code review comment for lp:~hbee/openobject-addons/7.0-merge_purchase_requisitions_wkf_fix

Oh, I can think of one issue now, when looking at this branch: https://code.launchpad.net/~openerp-dev/openobject-addons/7.0-opw-593185-rha/+merge/166651 (merged in OCB). This cleans up requisitions when procurements are cancelled. That is obviously not compatible with merged requisitions. It should probably be refactored to raise an error saying that the procurement can only be cancelled once the requisition has been cleaned up manually if there are more than one lines on the requisition.