MTA-STS support for Exim (Cernko, Patrick)

There is a Github project MTASTS-EXIM-PERL, that adds support for MTA-STS in Exim. Unfortunately, the project seems orphaned: no commits since 2019, open issue since 2023-03-01. Additionally, it only supports the sending part and not the reporting as described in RFC 8460.

I have forked the project to fixed the open issue and added a reporting part.

The current version of my MTASTS-EXIM-PERL can be found here:

• https://gitlab.mpi-klsb.mpg.de/pcernko/MTASTS-EXIM-PERL