When parsing XML to import invoice, different edi will need to find records for partner, product and taxes based on the values on the xml. The helpers avoids code duplication.
- E-FFF import moved from l10n_be_edi into a generic UBL import.
- [FIX] when importing if LineExtensionAmount is set but not PriceUnit on a move line, the price was not imported.
- Added export to generic UBL 2.1.