Noffle - news server Code

which optionally postpones adding a message ID to the upstream server.
If this is done, post-locally must be off.

This is to deal with an upstream server troubling Jan. It usually (but
not always) rejects posts with a Noffle message ID.

I have changed Jan's original option of 'add-message-id-if-missing'
for consistency with 'replace-messageid' and added the manual page entry.

See SourceForge feature request 1513395.