v2.2.25 release candidate released

[Timo Sirainen]

http://dovecot.org/releases/2.2/rc/dovecot-2.2.25.rc1.tar.gz
http://dovecot.org/releases/2.2/rc/dovecot-2.2.25.rc1.tar.gz.sig

Quite a lot of changes. Please test out before the final v2.2.25 release, which I'm planning for tomorrow. Especially the new lib-dcrypt might have compiling problems with some OpenSSL versions.

	* lmtp: Start tracking lmtp_user_concurrency_limit and reject already
	  at RCPT TO stage. This avoids MTA unnecessarily completing DATA only
	  to get an error.
	* doveadm: Previously only mail settings were read from protocol
	  doveadm { .. } section. Now all settings are.

	+ quota: Added quota_over_flag_lazy_check setting. It avoids checking
	  quota_over_flag always at startup. Instead it's checked only when
	  quota is being read for some other purpose.
	+ auth: Added a new auth policy service:
	  http://wiki2.dovecot.org/Authentication/Policy
	+ auth: Added PBKDF2 password scheme
	+ auth: Added %{auth_user}, %{auth_username} and %{auth_domain}
	+ auth: Added ":remove" suffix to extra field names to remove them.
	+ auth: Added "delay_until=<timestamp>[+<max random secs>]" passdb
	  extra field. The auth will wait until <timestamp> and optionally some
	  randomness and then return success.
	+ dict proxy: Added idle_msecs=<n> parameter. Support async operations.
	+ Performance improvements for handling large mailboxes.
	+ Added lib-dcrypt API for providing cryptographic functions.
	+ Added "doveadm mailbox update" command
	+ imap commands' output now includes timing spent on the "syncing"
	  stage if it's larger than 0.
	+ cassandra: Added metrics=<path> to connect setting to output internal
	  statistics in JSON format every second to <path>.
	+ doveadm mailbox delete: Added -e parameter to delete only empty
	  mailboxes. Added --unsafe option to quickly delete a mailbox,
	  bypassing lazy_expunge and quota plugins.
	+ doveadm user & auth cache flush are now available via doveadm-server.
	+ doveadm service stop <services> will stop specified services while
	  leaving the rest of Dovecot running.
	+ quota optimization: Avoid reading mail sizes for backends which
	  don't need them (count, fs, dirsize)
	+ Added mailbox { autoexpunge_max_mails=<n> } setting.
	+ Added welcome plugin: http://wiki2.dovecot.org/Plugins/Welcome
	+ fts: Added fts_autoindex_exclude setting.
	- v2.2.24's MIME parser was assert-crashing on mails having truncated
	  MIME headers.
	- auth: With multiple userdbs the final success/failure result wasn't
	  always correct. The last userdb's result was always used.
	- doveadm backup was sometimes deleting entire mailboxes unnecessarily.
	- doveadm: Command -parameters weren't being sent to doveadm-server.
	- If dovecot.index read failed e.g. because mmap() reached VSZ limit,
	  an empty index could have been opened instead, corrupting the
	  mailbox state.
	- imapc: Fixed EXPUNGE handling when imapc_features didn't have modseq.
	- lazy-expunge: Fixed a crash when copying failed. Various other fixes.
	- fts-lucene: Fixed crash on index rescan.
	- auth_stats=yes produced broken output
	- dict-ldap: Various fixes
	- dict-sql: NULL values crashed. Now they're treated as "not found".