gnu: python-tornado: Update to 4.3.

* gnu/packages/python.scm (python-tornado): Update to 4.3.
[native-inputs]: Add python-backports-abc.
(python2-tornado)[inputs]: Add python2-singledispatch.

gnu: Add python-backports-abc.

* gnu/packages/python.scm (python-backports-abc): New variable.

gnu: bitlbee: Update to 3.4.1.

* gnu/packages/patches/bitlbee-configure-doc-fix.patch: Delete file.
* gnu-system.am (dist_patch_DATA): Add it.
* gnu/packages/messaging.scm (bitlbee): Update to 3.4.1.
[source]: Remove patch.

grafts: Consider all the outputs in the graft mapping.

Before that, outputs of a derivation could be left referring to the
ungrafted version of the derivation.

* guix/grafts.scm (graft-derivation)[outputs]: Change to a list of
name/file pairs.
* guix/grafts.scm (graft-derivation)[build]: Add 'old-outputs' variable
and use it when computing 'mapping'.  Use 'mapping' directly.
* tests/grafts.scm ("graft-derivation, multiple outputs"): New test.

grafts: Slight simplification.

* guix/grafts.scm (graft-derivation)[output-names]: Use
'derivation-output-names'.

grafts: Make sure files are not created world-writable.

* guix/build/graft.scm (rewrite-directory): Add 'umask' call.

gnu: btrfs-progs: Update to 4.4.1.

* gnu/packages/linux.scm (btrfs-progs): Update to 4.4.1.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>

gnu: scribus: Update to 1.5.1.

* gnu/packages/scribus.scm (scribus): Update to 1.5.1.
[source]: Remove patch.
* gnu/packages/patches/scribus-qobject.patch: Delete file.
* gnu-system.am (dist_patch_DATA): Remove it.

gnu: arandr: Add "xrandr" to inputs.

* gnu/packages/xdisorg.scm (arandr)[inputs]: Add "xrandr".
[arguments]: Add build phase "make-xrandr-available" to ensure "xrandr"
executable is found at runtime.

gnu: Fix misplaced commas (unquote).

Fix many occurrences of comma (unquote) being placed immediately after the
previous list item, e.g. ("ncurses", ncurses) in the inputs.

* gnu/packages/base.scm (patch, gnu-make),
  gnu/packages/bioinformatics.scm (hmmer),
  gnu/packages/bittorrent.scm (aria2),
  gnu/packages/compression.scm (pbzip2),
  gnu/packages/databases.scm (recutils),
  gnu/packages/fonts.scm (font-terminus),
  gnu/packages/freedesktop.scm (xdg-utils, elogind),
  gnu/packages/games.scm (gnujump),
  gnu/packages/gnome.scm (libidl, gnumeric, eog, gedit),
  gnu/packages/gnunet.scm (gnunet),
  gnu/packages/gnuzilla.scm (mozjs, nspr),
  gnu/packages/gtk.scm (gtksourceview, gdk-pixbuf),
  gnu/packages/lua.scm (lua),
  gnu/packages/openstack.scm (python-swiftclient),
  gnu/packages/perl.scm (perl-json-any),
  gnu/packages/polkit.scm (polkit-qt),
  gnu/packages/python.scm (wrap-python3, python-oauthlib)
  (python-mccabe-0.2.1, python-contextlib2, python2-rauth),
  gnu/packages/qt.scm (qtkeychain),
  gnu/packages/ruby.scm (ruby-nokogiri),
  gnu/packages/screen.scm (screen),
  gnu/packages/ssh.scm (libssh),
  gnu/packages/video.scm (ffmpeg, mplayer),
  gnu/packages/vim.scm (vim),
  gnu/packages/xdisorg.scm (redshift),
  gnu/packages/xfce.scm (xfce4-panel, xfce4-settings),
  gnu/packages/xnee.scm (xnee),
  gnu/packages/xorg.scm (font-adobe100dpi, font-adobe75dpi),
  gnu/packages/zsh.scm (zsh): Fix misplaced commas (unquote).

gnu: Add emacs-god-mode.

* gnu/packages/emacs.scm (emacs-god-mode): New variable.

gnu: Add gtklick.

* gnu/packages/music.scm (gtklick): New variable.

gnu: python2-pygtk: Add libglade to inputs.

* gnu/packages/gtk.scm (python2-pygtk)[inputs]: Add "libglade".

gnu: Add pyliblo.

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

gnu: linux-libre-4.1: Update to 4.1.18.

* gnu/packages/linux.scm (linux-libre-4.1): Update to 4.1.18.

gnu: linux-libre: Update to 4.4.3.

* gnu/packages/linux.scm (linux-libre): Update to 4.4.3.

import: Add github-updater.

* guix/import/github.scm: New file.
* guix/scripts/refresh.scm (%updaters): Add %GITHUB-UPDATER.
* doc/guix.texi (Invoking guix refresh): Mention it.
* Makefile.am (MODULES): Add gnu/import/github.scm.

store: 'path-info-deriver' is #f when there is no deriver.

* guix/store.scm (read-path-info): Use #f when we get the empty string
for DERIVER.
* guix/scripts/publish.scm (narinfo-string): Adjust accordingly.
* tests/store.scm ("path-info-deriver"): New test.

grafts: Add record type printer.

* guix/grafts.scm (write-graft): New procedure.  Register it as a
printer for <graft>.

doc: Capitalize section title.

* doc/guix.texi (Running GuixSD in a VM): Capitalize section title.