This module analyzses a Mail::Internet object and returns a
Mail::ListDetector::List object representing the mailing list the
email was sent to, if any.

The RFC2369 mailing list detector is also capable of matching some
Mailman and Ezmlm messages. It is deliberately checked last to allow
the more specific Mailman and Ezmlm parsing to happen first, and
more accurately identify the type of mailing list involved.