[Dovecot] v2.2.rc4 released

http://dovecot.org/releases/2.2/rc/dovecot-2.2.rc4.tar.gz http://dovecot.org/releases/2.2/rc/dovecot-2.2.rc4.tar.gz.sig

A lot of small random fixes. Some last minute major cleanups/fixes to lib-http and lib-ssl-iostream error handling, which makes them much easier to debug if something goes wrong (so e.g. if https site has invalid certificate, the caller gets error message saying that, including the part of the cert that couldn't be validated).

I don't have anything important left in my v2.2 TODO. It passes all my tests. So I'm hoping for v2.2.0 release any day now.

+ Added "doveadm replicator" commands
- Larger changes to lib-http and lib-ssl-iostream error handling.
  The API caller can now get the exact error message as a string.
- Various bugfixes to LDAP changes in rc3