Log Message:
Update postfix to 2.11.0.  Quote from release announce:

The main changes in no particular order are:

  * Support for PKI-less TLS server certificate verification with
    DANE (DNS-based Authentication of Named Entities) where the CA
    public key or the server certificate is identified via DNSSEC
    lookup. This requires a DNS resolver that validates DNSSEC
    replies. The problem with conventional PKI is that there are
    literally hundreds of organizations world-wide that can provide
    a certificate in anyone's name. DANE limits trust to the people
    who control the target DNS zone and its parent zones.

  * Support for LMDB databases. Originally developed as part of
    OpenLDAP, LMDB is the first persistent Postfix database that
    can be shared among multiple writers such as postscreen daemons
    (Postfix already supported shared non-persistent memcached
    caches). Postfix currently requires LMDB version 0.9.11 or
    later. See LMDB_README for details and limitations.

  * A new postscreen_dnsbl_whitelist_threshold feature to allow
    clients to skip postscreen tests based on their DNSBL score.
    This can eliminate email delays due to "after 220 greeting"
    protocol tests, which otherwise require that a client reconnects
    before it can deliver mail. Some providers such as Google don't
    retry from the same IP address, and that can result in large
    email delivery delays.

  * The recipient_delimiter feature now supports different delimiters,
    for example both "+" and "-". As before, this implementation
    recognizes exactly one delimiter character per email address,
    and exactly one address extension per email address.

  * Advanced master.cf query/update support to access service
    attributes as "name = value" pairs. For example to turn off
    chroot on all services use "postconf -F '*/*/chroot = n'", and
    to change/add a "-o name=value" setting use "postconf -P
    smtp/inet/name = value". This was developed primarily to allow
    automated tools to manage Postfix systems without having to
    parse Postfix configuration files.