* gnu/packages/version-control.scm (cgit): New variable.

This updates 58f0aae5.

* gnu/packages/package-management.scm (guix): Set to GUIX-0.10.0.

* gnu/packages/package-management.scm (guix-0.8.3): Rename to...
(guix-0.10.0): ... this.  Adjust users.
(guix): Set to GUIX-0.10.0.

Suggested by Leo Famulari and others.

* guix/scripts/system.scm (maybe-suggest-running-guix-pull): New
procedure.
(perform-action): Call it when ACTION is 'reconfigure.

Suggested by Chris Marusich <cmmarusich@gmail.com>.

* doc/guix.texi (Limitations): Increase package count.

This allows GuixSD to default to the right list of URLs, with
mirror.hydra.gnu.org coming first.

Reported by Chris Marusich <cmmarusich@gmail.com>.

* guix/store.scm (%default-substitute-urls): Prepend
"mirror.hydra.gnu.org."

Suggested by Chris Marusich <cmmarusich@gmail.com>.

* doc/guix.texi (Proceeding with the Installation): Explain why the
config file should be on the target file system.

Suggested by Chris Marusich <cmmarusich@gmail.com>.

* doc/guix.texi (Preparing for Installation): Add "-v" for dhclient.

Based on a suggestion by Chris Marusich <cmmarusich@gmail.com>.

* doc/guix.texi (System Installation): Suggest running "info info".

Suggested by Chris Marusich <cmmarusich@gmail.com>.

* doc/guix.texi (Proceeding with the Installation): Clarify what
'cow-store' is about.

Suggested by Jan Nieuwenhuizen <janneke@gnu.org>.

* doc/guix.texi (Preparing for Installation): Make it clear that
networking is required.

* doc/guix.texi (Security Updates): Add paragraph on the big picture of
security updates.  Cross-reference 'guix lint'.
(Invoking guix lint): Add CVE URLs.

* gnu/packages/music.scm (qtractor): Update to 0.7.5.

* gnu/packages/music.scm (nose)[native-inputs]: Add python-nose.
[arguments]: Replace 'check' and use python-nose.

Switching to execlp means that the process spawned in a container is PID
1, which obsoleted one of the 'guix environment --container' tests
because the init process can't be killed in the usual manner.

* guix/scripts/environment.scm (launch-environment/fork): New procedure.
(launch-environment): Switch from system* to execlp.  Add handler for
SIGINT.
(guix-environment): Use launch-environment/fork.
* tests/guix-environment-container.sh: Replace abnormal exit test with
one that works now that the spawned process is PID 1.

* gnu/packages/music.scm (pyechonest)[description]: Remove "open source" from
the description.

* gnu/packages/maths.scm (pspp): Update to 0.10.0.
[inputs]: Switch gtk+-2 to gtk+, gtksourceview-2 to gtksourceview.

* gnu/packages/sdl.scm (sdl2-ttf): Update to 2.0.14 and remove bundled
  libraries from source tarball.

* gnu/packages/sdl.scm (sdl2-image): Update to 2.0.1.

* gnu/packages/sdl.scm (sdl2-mixer): Update to 2.0.1 and remove bundled
  libraries in source tarball.

* gnu/packages/sdl.scm (sdl-mixer)[inputs]: Add libmodplug.

* gnu/packages/sdl.scm (sdl2): Update to 2.0.4.

* doc/guix.texi (Preparing for Installation): Fix typo.

* gnu/packages/kodi.scm (crossguid)[source]: Set explicit file-name to
  satisfy linter.

* guix/scripts/environment.scm (launch-environment/container): Change
$HOME to the current user's home directory instead of
/homeless-shelter.  Create a dummy /etc/passwd with a single entry for
the current user.
* doc/guix.texi ("invoking guix environment"): Add a note about the
dummy home directory and /etc/passwd.

* doc/guix.texi (Features): Mention trust and 'guix challenge'.

Suggested by myglc2 <myglc2@gmail.com>.

* doc/guix.texi (Introduction): Rephrase to mention features and use
cases first, and foundations last.
(Features): Mention "GuixSD".
(Utilities): Change intro: not all the tools are for packagers.

This reverts commit 64588765.

* gnu/packages/package-management.scm (diffoscope): Update to 51.

* gnu/packages/python.scm (python-atomicwrites, python2-atomicwrites):
Update to 1.0.0.

* gnu/packages/xml.scm (expat)[replacement]: New field.
(expat-2.1.1): New variable.

Fixes <http://bugs.gnu.org/22612>.
Reported by Danny Milosavljevic <dannym@scratchpost.org>.

* tests/syscalls.scm ("network-interfaces returns one or more
interfaces"): Accept 'interface-address' value of #f.

Reported by Danny Milosavljevic <dannym@scratchpost.org>
in <http://debbugs.gnu.org/cgi/bugreport.cgi?bug=22612#16>.

* guix/build/syscalls.scm (write-interface): Check whether ADDRESS is
true.

* gnu/packages/package-management.scm (guix-devel): Update to dd213082.

* gnu/packages/music.scm (lilypond)[arguments]: Patch configure script
  to find actual fontforge version.

* gnu/packages/databses.scm (postgresql): substitute /bin/sh
with location of bash binary.

* gnu/packages/admin.scm (htop): Update to 2.0.1.