Move cost price to product level instead of template

issue6515
review41321002

tests/test_customs.py

@@ -195,7 +195,6 @@ class CustomsTestCase(ModuleTestCase):
         template = Template(name='Test',
             default_uom=unit,
             list_price=Decimal(0),
-            cost_price=Decimal(0),
             tariff_codes=[
                 Product_TariffCode(tariff_code=tariff),
                 ])