Updated gnupg21 to 2.1.20.

Based on PR 52165 by Jonathan Schleifer.

Noteworthy changes in version 2.1.20 (2017-04-03)
-------------------------------------------------

  * gpg: New properties 'expired', 'revoked', and 'disbaled' for the
    import and export filters.

  * gpg: New command --quick-set-primary-uid.

  * gpg: New compliance field for the --with-colon key listing.

  * gpg: Changed the key parser to generalize the processing of local
    meta data packets.

  * gpg: Fixed assertion failure in the TOFU trust model.

  * gpg: Fixed exporting of zero length user ID packets.

  * scd: Improved support for multiple readers.

  * scd: Fixed timeout handling for key generation.

  * agent: New option --enable-extended-key-format.

  * dirmngr: Do not add a keyserver to a new dirmngr.conf.  Dirmngr
    uses a default keyserver.

  * dimngr: Do not treat TLS warning alerts as severe error when
    building with GNUTLS.

  * dirmngr: Actually take /etc/hosts in account.

  * wks: Fixed client problems on Windows.  Published keys are now set
    to world-readable.

  * tests: Fixed creation of temporary directories.

  * A socket directory for a non standard GNUGHOME is now created on
    the fly under /run/user.  Thus "gpgconf --create-socketdir" is now
    optional.  The use of "gpgconf --remove-socketdir" to clean up
    obsolete socket directories is however recommended to avoid
    cluttering /run/user with useless directories.

  * Fixed build problems on some platforms.

Noteworthy changes in version 2.1.19 (2017-03-01)
-------------------------------------------------

  * gpg: Print a warning if Tor mode is requested but the Tor daemon
    is not running.

  * gpg: New status code DECRYPTION_KEY to print the actual private
    key used for decryption.

  * gpgv: New options --log-file and --debug.

  * gpg-agent: Revamp the prompts to ask for card PINs.

  * scd: Support for multiple card readers.

  * scd: Removed option --debug-disable-ticker.  Ticker is used
    only when it is required to watch removal of device/card.

  * scd: Improved detection of card inserting and removal.

  * dirmngr: New option --disable-ipv4.

  * dirmngr: New option --no-use-tor to explicitly disable the use of
    Tor.

  * dirmngr: The option --allow-version-check is now required even if
    the option --use-tor is also used.

  * dirmngr: Handle a missing nsswitch.conf gracefully.

  * dirmngr: Avoid PTR lookups for keyserver pools.  The are only done
    for the debug command "keyserver --hosttable".

  * dirmngr: Rework the internal certificate cache to support classes
    of certificates.  Load system provided certificates on startup.
    Add options --tls, --no-crl, and --systrust to the "VALIDATE"
    command.

  * dirmngr: Add support for the ntbtls library.

  * wks: Create mails with a "WKS-Phase" header.  Fix detection of
    Draft-2 mode.

  * The Windows installer is now build with limited TLS support.

  * Many other bug fixes and new regression tests.

  See-also: gnupg-announce/2017q1/000402.html


(wiz)