[Dovecot] v2.2.4 released

http://dovecot.org/releases/2.2/dovecot-2.2.4.tar.gz http://dovecot.org/releases/2.2/dovecot-2.2.4.tar.gz.sig

OK, this should be a pretty good and stable version.

    + doveadm: Added "flags" command to modify message flags.
    + doveadm: Added "deduplicate" command to expunge message duplicates.
    + dsync: Show the state in process title with verbose_proctitle=yes.
    - imap/pop3 proxy: Master user logins were broken in v2.2.3
    - sdbox/mdbox: A corrupted index header with wrong size was never
      automatically fixed in v2.2.3.
    - mbox: Fixed assert-crashes related to locking.