Feature Request: DKIM keys from hdd

[Franz-Heinz]

Since admins that value the privacy of their users may/should change DKIM keys on a regular bases it seems reasonable for journalists to make local backups of the DKIM keys used by goverment (and other important) servers to be able to verify emails that may be leaked a long time after DKIM keys have been changed.

Ideally the tool should be able to use this local backups from hdd as a source to verify signatures against.