A function field summary is added which takes the first line of description
field. This is useful to identify line without product (only with description)
in the list.
issue9695
review292431002
The purchase line does not required to have a product, so the purchase request
should behave the same. A description field is added to be used instead of the
product name as purchase line description.
The unit price is only computed if it is not yet set and if there is a product.
issue5670
review27431002
Maxime Richez