Extended getCompletionDate to support the case in which the CompletionDate is found on the delivery line, whenever simulation movement has not yet been built (but is it really useful ?)

git-svn-id: https://svn.erp5.org/repos/public/erp5/sandbox/amount_generator@36054 20353a03-c40f-0410-a6d1-a30d3c3de9de