DIIA should respect PDF-internal attachments

SER themselves did send us invoices containing attachments in their eInvoice PDFs.

DOXiS DIIA they installed simply ignored those attachments.

After talking to SER, their 'solution' was to not send us PDFs with attachments anymore, but separate files - and we have not heard anything else regarding that issue.

That is not a real solution.

We fixed it ourselves in the import agent - but it should be part of how DOXiS handles PDFs, probably in DCES. As well as in Rendition Service, see also: https://ser.ideas.aha.io/ideas/IDEA-I-267