Lp port mp sale markup

This is a port of the merge proposal on launchpad :

https://code.launchpad.net/~camptocamp/sale-financial/7.0-port-sale_markup/+merge/214061




Can you try to give a method name that better describes what the test does?

I know it is not easy, but "create_sale_order" is not what it does. For tests names, it is a good idea to use a very long name if needed (it will be shown on test failures, and you don't have to repeat it elsewhere).