[Spambayes] Corrupt database

[Tony Meyer]

> Oh yeah, I forgot the Outlook plugin store()s pretty 
> frequently.  Do the other long-running apps?

sb_server currently store()s at the end of processing each review page,
although Tim has suggested that it'd be better for the db to store() after
learning each message.  sb_imapfilter only store()s at the end of all the
training (it would probably be better to store() at least after training
each folder).

=Tony Meyer