[Dovecot] v2.1.rc5 released

[Timo Sirainen]

http://dovecot.org/releases/2.1/rc/dovecot-2.1.rc5.tar.gz
http://dovecot.org/releases/2.1/rc/dovecot-2.1.rc5.tar.gz.sig

I'm still lagging behind reading emails. v2.1.0 will be released after I've finished that. RC5 is already stable and used in production, but I want to make sure that I haven't missed anything important that was reported previously. Most of the recent fixed bugs existed also in v2.0 series.

Changes since rc3:

        * Temporary authentication failures sent to IMAP/POP3 clients
          now includes the server's hostname and timestamp. This makes it
          easier to find the error message from logs.

        + auth: Implemented support for Postfix's "TCP map" sockets for
          user existence lookups.
        + auth: Idling auth worker processes are now stopped. This reduces
          error messages about MySQL disconnections.
        - director: With >2 directors ring syncing might have stalled during
          director connect/disconnect, causing logins to fail.
        - LMTP client/proxy: Fixed potential hanging when sending (big) mails
        - Compressed mails with external attachments (dbox + SIS + zlib) failed
          sometimes with bogus "cached message size wrong" errors.

(I skipped rc4 release, because I accidentally tagged it too early in hg.)