[ADD] account_facturx: add import/export invoice using the Factur-x standard

Factur-x is the e-invoicing standard in vigor in FR & DE and, by extension, it will probably become the standard in Europe. Thus this will be used as default e-invoicing standard by Odoo.

The idea is simple:
  * when printing your customer invoice report (not in draft ofc), a Factur-x xml file is generated and embedded inside the PDF.
  * when importing supplier bills in the form of PDF files, we detect if any Factur-x xml file is attached and complete the data of the draft vendor bill accordingly. This is done during the message_post() function.

/!\ To be compliant with the Factur-x standard, the PDF should be PDF/A-3b compliant. (See: http://fnfe-mpe.org/wp-content/uploads/2018/07/1.-FACTUR-X-V1.1-2018-07-24-FR.pdf chapter 6)
    However, wkhtmltopdf is not PDF/A compliant and then, the generated PDF report are not fully compliant with the Factur-x standard.

Was task: 1859277
Was PR #25508

0 files changed, 0 insertions, 0 deletions