Log Message:
Update dovecot-pigeonhole to 0.4.12.
It is v0.4.12 release of Pigeonhole for Dovecot v2.2.21.

v0.4.12 06-02-2016 Stephan Bosch <stephan@rename-it.nl>

	+ Implemented the Sieve extracttext extension (RFC 5703; Section 7). It is now
	  possible to extract body text from a message into a variable.
	* Increased ABI version due to changes in the Sieve interpreter's object
	  definitions.
	- multiscript: Fixed bug in handling of (implicit) keep; final keep action was
	  always executed as though there was a failure. This caused the keep action
	  to revert back to the initial message, causing editheader actions to be
	  ignored.
	- managesieve-login: Fixed proxy to allow SASL mechanisms other than PLAIN.
	  Before, the proxy would fail if the server did not support the PLAIN
	  mechanism.
	- ldap storage: Prevent segfault occurring when assigning certain (global)
	  configuration options.

v0.4.11 08-01-2016 Stephan Bosch <stephan@rename-it.nl>

	- Sieve mime extension: Fixed the header :mime :anychild test to work properly
	  outside a foreverypart loop.
	- Several fixes in message body part handling:
	  - Fixed assert failure occurring when text extraction is attempted on a
	    empty or broken text part.
	  - Fixed assert failure in handling of body parts that are converted to text.
	  - Fixed header unfolding for (mime) headers parsed from any mime part.
	  - Fixed trimming for (mime) headers parsed from any mime part.
	  - Fixed erroneous changes to the message part tree structure performed when
	    re-parsing the message.
	- LDA Sieve plugin: Fixed logging of actions; sometimes the configured log
	  format was not followed.
	- LDA Sieve plugin: Fixed bug in error handling of script storage
	  initialization.
	- Sieve Extprograms plugin: Ignored ENOTCONN error in shutdown(fd, SHUT_WR)
	  call.
	- Fixed duplication of discard actions in the script result. Each discard was
	  counted as a separate action, which means that action limit would be crossed
	  too early.
	- Made sure that quota errors never get logged as errors in syslog.
	- Fixed handling of implicit keep for a partially executed transaction that
	  yielded a temporary failure.
	- Fixed handling of global errors. If master and user error handler were
	  identical, in some cases the log message could be lost.
	- Fixed AIX compile issue in message body parser.

v0.4.10 13-12-2015 Stephan Bosch <stephan@rename-it.nl>

	+ Implemented the Sieve mime and foreverypart extensions (RFC 5703). These
	  are fully implemented. The interaction with the editheader extension needs
	  some work, but this should not influence most uses; i.e., changes by the
	  editheader extension are not always visible using foreverypart/mime.
	+ Sieve body extension: Properly implemented the `:text' body transform. It
	  now extracts text for HTML message parts.
	+ Sieve enotify extension: mailto method: Implemented the
	  sieve_notify_mailto_envelope_from setting. This allows configuring the
	  source of the notification sender address for e-mail notifications. This is
	  similar to what already can be configured for redirect.
	+ Added a sieve_enabled (defaults to 'yes') setting that allows explicitly
	  disabling Sieve processing for particular users. This used to be possible by
	  setting `sieve=', but ever since the sieve_before, sieve_after and
	  sieve_default settings were added, this method was not reliable anymore.
	- variables extension: Fixed handling of empty string by the `:length' set
	  modifier. An empty string yielded an empty string rather than "0".
	- Fixed memory leak in the Sieve script byte code dumping facility. Extension
	  contexts were never actually freed.
	- Fixed handling of implicit keep when the last Sieve script is a global one.
	  In that case the implicit keep action was executed in global context, which
	  could mean that trivial (quota) errors ended up in the system log file,
	  rather than the user log file.
	- doveadm sieve plugin: Fixed crashes caused by incorrect context allocation
	  in the sieve command implementations.