[Dovecot] Adding capacity by simply migrating to dovecot -- thank you

[Benjamin Connelly]

> If you still want to reduce disk IO, you can also try (if you haven't
> already):
>
> - deliver: http://wiki.dovecot.org/LDA/Indexing
> - maildir_very_dirty_syncs=yes:
> http://wiki.dovecot.org/MailLocation/Maildir

We did switch from maildrop (and courier authd and cyrus sasl) to just  
dovecot (+sieve +manage sieve, a great simplification to build and  
maintain) and will ponder very dirty syncs. . .