* gnu/packages/game-development.scm (gzochi): New variable.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

* gnu/packages/compression.scm (pigz): New variable.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

Fixes <http://bugs.gnu.org/21516>.
Reported by Andreas Enge <andreas@enge.fr>.

* gnu/packages/lsh.scm (lsh)[arguments]: In 'pre-configure' phase,
  change 'src/lsh-authorize' to use the absolute file name of
  'sexp-conv'.

Suggested by Mark H Weaver <mhw@netris.org>.

* guix/scripts/gc.scm (show-help, %options): Add --list-failures and
  --clear-failures.
  (guix-gc): Honor them.
* doc/guix.texi (Invoking guix gc): Document them.
  (Invoking guix-daemon): Mention them.

Suggested by Mark H Weaver <mhw@netris.org>.

* guix/store.scm (query-failed-paths, clear-failed-paths): New
  procedures.
* tests/guix-daemon.sh: Add test with daemon started with
  --cache-failures.

* guix/tests.scm (open-connection-for-tests): Add optional FILE
  parameter; pass it to 'open-connection'.

* gnu/packages/bioinformatics.scm (bio-blastxmlparser): New variable.

* gnu/packages/statistics.scm (r-data.table): New variable.

* gnu/packages/statistics.scm (r-chron): New variable.

* gnu/packages/web.scm (r-servr): New variable.

* gnu/packages/web.scm (r-jsonlite): New variable.

* gnu/packages/web.scm (r-httpuv): New variable.

This is a followup to commit ba7d6c76.

* doc/guix.texi (Synopses and Descriptions): Fix spelling.

Fixes a regression introduced in 5d8d8f3b.

* guix/scripts/lint.scm (check-description-style): When no exception is
  thrown in 'check-texinfo-markup', return the rendered description.

* doc/guix.texi (Synopses and Descriptions): Warn about special
  characters in Texinfo.  Indicate how to help the translators.

* gnu/packages/xdisorg.scm (arandr): New variable.

* gnu/packages/video.scm (avidemux)[inputs]: Replace qt-4 by qt.
  [arguments]: Add build flag.

* gnu/packages/code.scm (global): Update to 6.5.1.

* gnu/packages/gnunet.scm (libmicrohttpd): Update to 0.9.43.

* gnu/packages/disk.scm (ddrescue): Update to 1.20.

* gnu/packages/telephony.scm (sipwitch): Update to 1.9.10.

* gnu/packages/telephony.scm (ucommon): Update to 6.6.0.

* gnu/packages/parallel.scm (parallel): Update to 20150922.

* gnu/packages/search.scm (xapian): Update to 1.2.21.

* emacs/guix-guile.el (guix-guile-keyword-regexp): New function.
* emacs/guix-devel.el (guix-devel-faces): New custom group.
  (guix-devel-modify-phases-keyword): New face.
  (guix-devel-modify-phases-keyword-regexp,
  guix-devel-font-lock-keywords): New variables.
  (guix-devel-modify-phases-font-lock-matcher,
  guix-devel-modify-phases-font-lock-pre): New functions.
  (guix-devel-mode): Adjust to add/remove font-lock-keywords.

* gnu/packages/mail.scm (mu): Update to 0.9.13.

* gnu/packages/mpd.scm (ncmpcpp): Update to 0.6.7.

* gnu/packages/patches/qemu-CVE-2015-3209.patch,
  gnu/packages/patches/qemu-CVE-2015-4037.patch,
  gnu/packages/patches/qemu-CVE-2015-4103.patch,
  gnu/packages/patches/qemu-CVE-2015-4104.patch,
  gnu/packages/patches/qemu-CVE-2015-4105.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt1.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt2.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt3.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt4.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt5.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt6.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt7.patch,
  gnu/packages/patches/qemu-CVE-2015-4106-pt8.patch,
  gnu/packages/patches/qemu-CVE-2015-5745.patch: Delete files.
* gnu/packages/patches/qemu-CVE-2015-6855.patch: New file.
* gnu-system.am (dist_patch_DATA): Add the new patch and delete the old ones.
* gnu/packages/qemu.scm (qemu-headless): Update to 2.4.0.1.  Add the new patch
  and delete the old ones.

* guix/scripts/lint.scm (check-description-style): Set 'field' parameter
  when emitting a warning in 'check-texinfo-markup'.  Catch any error
  that may occur in during the 'texi->plain-text' conversion.  This is a
  followup to commit 2748ee3b.

* gnu/packages/ibus.scm (ibus)[inputs]: Add the required gtk+-3.

Fixes the wrong-type-arg exception initially reported
at <http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19976#5>
by Ricardo Wurmus <rekado@elephly.net>.

* guix/http-client.scm (read-chunk-header): Backport Guile commit 53b8d5f.

* gnu/packages/compression.scm (squashfs-tools): New variable.

* guix/scripts/offload.scm (send-files): Use gzip --fast instead of xz.

* guix/utils.scm (compressed-output-port,
  call-with-compressed-output-port): Add #:options parameter and honor
  it.

* gnu/packages/messaging.scm (gajim): New variable.

* gnu/packages/messaging.scm (python-nbxmpp, python2-nbxmpp): New
  variables.

* gnu/packages/gnupg.scm (python-gnupg, python2-gnupg): New variables.

* gnu/packages/python.scm (python-pyopenssl, python2-pyopenssl): New
  variables.

* gnu/packages/python.scm (python-cryptography, python2-cryptography):
  New variables.