[Dovecot] v2.2.rc5 released

http://dovecot.org/releases/2.2/rc/dovecot-2.2.rc5.tar.gz http://dovecot.org/releases/2.2/rc/dovecot-2.2.rc5.tar.gz.sig

One more API change that required also a Pigeonhole modification. A few other random fixes. I'm planning on making v2.2.0 release on Monday. Please test before that. :)