[Dovecot] Convert plugin

[Jay Chandler]

convert_mail = mbox:%h/mail

    Convert plugin. If set, specifies the source storage path which is
    converted to destination storage (mail_location) when the user logs
    in. The existing mail directory is renamed to <dir>-converted.

I'm not entirely clear on what this does.  If someone can clarify for 
me, I'll update the Wiki.

I'm hoping it'll allow me to convert from mbox to Maildir-- otherwise 
I'm looking at a weekend of downtime when that project comes due...

-- 
Jay Chandler
Network Administrator, Chapman University
714.628.7249 / chandler at chapman.edu
Today's Excuse: high pressure system failure