Don't require calling Message#message before original_message.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Delay parsing of message in extruder-match.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Provide an option for a dummy sender when generating mboxes.

Parsing the actual mail can be very expensive when handling large numbers of
messages.  Provide an option, --dummy-sender, to fill in a dummy sender when
generating an mbox, instead of parsing the mail to determine the sender from
that.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Parse dates from Postfix received headers.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>