- setSourceDebit(-1) will set cancellation amount
 - inventory API treat a movement of quantity -1 as an input movement if
   cancellation amount is set
 - s/getSource/DestinationTotalAssetDebit/Credit also support cancellation amount like
   s/getSource/DestinationDebit/Credit



git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@27694 20353a03-c40f-0410-a6d1-a30d3c3de9de