Run our own little SMTP server, attempt to parse all incoming messages. Currently only DMARC email support is implemented (both ZIP and gzip formats).
These originate from "report-uri" (not "report-to") tags in CSP headers, and appear as application/csp-report requests.
It can be either a scalar or a list, skip parsing it for now as it is unused.
Also, stop logging the client IP for email reports, where it's just going to be some email provider's reporting infrastructure.
