gnu: Switch ruby-pg to build with postgresql-9.6.

As the testsuite fails with the later version.

* gnu/packages/ruby.scm (ruby-pg)[inputs]: Switch postgresql to
  postgresql-9.6.

gnu: emacs-browse-at-remote: Patch for GNU Cgit support.

* gnu/packages/patches/emacs-browse-at-remote-cgit-gnu.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/emacs.scm (emacs-browse-at-remote)[source](patches): Use it.

gnu: clementine: Remove Spotify downloader.

Clementine has a button in the preference menu that allows downloading a
binary blob to add support for Spofify.  Let's remove this button.  It turns
out this is the only part of the code base that uses crypto++, let's remove
this dependency too.

* gnu/packages/music.scm (clementine)[arguments]: Remove crypto++ support. Set
HAVE_SPOTIFY_DOWNLOADER to FALSE.
[inputs]: Remove crypto++ input.
* gnu/packages/patches/clementine-remove-crypto++-dependency.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.

Signed-off-by: Leo Famulari <leo@famulari.name>

gnu: appstream-glib: Propagate some inputs.

* gnu/packages/glib.scm (appstream-glib)[inputs]: Move gcab, gdk-pixbuf,
util-linux to propagated-inputs.

gnu: samba: Update to 4.7.5.

* gnu/packages/samba.scm (samba): Update to 4.7.5.

gnu: zziplib: Update to 0.13.68.

* gnu/packages/patches/zziplib-CVE-2017-5974.patch,
gnu/packages/patches/zziplib-CVE-2017-5975.patch,
gnu/packages/patches/zziplib-CVE-2017-5976.patch,
gnu/packages/patches/zziplib-CVE-2017-5978.patch,
gnu/packages/patches/zziplib-CVE-2017-5979.patch,
gnu/packages/patches/zziplib-CVE-2017-5981.patch: Delete files.
* gnu/local.mk (dist_patch_DATA): Remove them.
* gnu/packages/compression.scm (zziplib): Update to 0.13.68.
[source](patches): Remove.
[arguments]: Remove #:parallel-tests?.  Set #:tests? #f.

services: avahi: Default to nss-mdns 0.10.

This works around <https://bugs.gnu.org/30396>.
Reported by George myglc2 Clemmer <myglc2@gmail.com>.

* gnu/packages/avahi.scm (nss-mdns-0.10): New variable.
* gnu/services/avahi.scm (avahi-service-type): Use it.

gnu: guile-sqlite3: Update to 0.0-3.1cd1dec.

* gnu/packages/guile.scm (guile-sqlite3): Update to 0.0-3.1cd1dec.

gnu: guix: Update snapshot to bc880f9.

* gnu/packages/package-management.scm (guix): Update to bc880f9.

gnu: mcron2: Install files to 'share/guile/site/2.2'.

Reported by Maxim Cournoyer <maxim.cournoyer@gmail.com>.

* gnu/packages/guile.scm (mcron2)[arguments]: In 'use-guile-2.2' phase,
substitute /share/guile/site/2.0.

ssh: Work around 'select' bug in Guile.

Fixes <https://bugs.gnu.org/30365>.

* guix/ssh.scm (remote-daemon-channel)[redirect]: Define 'select*' and
use it.

gnu: services: Add wesnothd service.

* gnu/services/games.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* doc/guix.texi (Game Services): Document the service.

gnu: Add wesnoth-server.

* gnu/packages/games.scm (wesnoth-server): New variable.

gnu: Add sipcalc.

* gnu/packages/admin.scm (sipcalc): New public variable.

gnu: mu: Use a fixed variant of tzdata for the mu tests.

* gnu/packages/mail.scm (mu)[inputs]: Remove tzdata.
[native-inputs]: Add tzdata-2017a.

gnu: mu: Update to 1.0.

* gnu/packages/mail.scm (mu): Update to 1.0.

Signed-off-by: Leo Famulari <leo@famulari.name>

gnu: audacity: Update to 2.2.1.

* gnu/packages/audio.scm (audacity): Update to 2.2.1.

gnu: postgresql: Update to 10.2 [CVE-2018-{1052,1053}].

* gnu/packages/databases.scm (postgresql): Update to 10.2.

gnu: linux-libre: Update to 4.15.2.

* gnu/packages/linux.scm (%linux-libre-version): Update to 4.15.2.
(%linux-libre-hash): Update hash.

gnu: linux-libre@4.14: Update to 4.14.18.

* gnu/packages/linux.scm (%linux-libre-4.14-version): Update to 4.14.18.
(%linux-libre-4.14-hash): Update hash.