Show shipped quantities when viewing costing batch row

for lines which came from invoice, we should know those quantities,
but possibly *not* the received quantities, if e.g. the line item
wasn't matched w/ PO

tailbone/views/purchasing/costing.py

@@ -128,6 +128,8 @@ class CostingBatchView(PurchasingBatchView):
         'size',
         'department_name',
         'case_quantity',
+        'cases_shipped',
+        'units_shipped',
         'cases_received',
         'units_received',
         'po_line_number',