gnu: Add openfoam.

*gnu/packages/patches/openfoam-4.1-cleanup.patch: New file
*gnu/packages/simulation.scm: New file
*gnu/local.mk (GNU_SYSTEM_MODULES): Add module.
(dist_patch_DATA): Add patch.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu: emacs-emms: Fix metadata retrieval for MP3 and FLAC files.

* gnu/packages/emacs.scm (emacs-emms): Reference find, mpg321 and metaflac by
their complete file path.
[inputs]: Add flac.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu: Add python-schedule.

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

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu: Add pydf.

* gnu/packages/disk.scm (pydf): New variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu: libzip: Fix building on 32-bit architectures.

* gnu/packages/compression.scm (libzip)[arguments]: New field, add phase
to skip tests which are known to have issues on 32-bit architectures.

gnu: linux-libre: Update to 4.13.2.

* gnu/packages/linux.scm (%linux-libre-version): Update to 4.13.2.
(%linux-libre-hash): Update hash.
(linux-libre, linux-libre-arm-generic): Remove patch.

gnu: linux-libre@4.9: Update to 4.9.50.

* gnu/packages/linux.scm (linux-libre-4.9): Update to 4.9.50.  Remove patch.

gnu: linux-libre@4.4: Update to 4.4.88.

* gnu/packages/linux.scm (linux-libre-4.4): Update to 4.4.88.  Remove patch.

gnu: Add gnucobol.

* gnu/packages/cobol.scm (gnucobol): New variable.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.

gnu: Update default gcc-objc and gcc-objc++.

* gnu/packages/gcc.scm (gcc-objc, gcc-objc++): Update default to 5.

gnu: Add gcc-objc++@7.

* gnu/packages/gcc.scm (gcc-objc++@7): New variable.

gnu: Add gcc-objc@7.

* gnu/packages/gcc.scm (gcc-objc@7): New variable.

gnu: Add gcc-objc++@6.

* gnu/packages/gcc.scm (gcc-objc++@6): New variable.

gnu: Add gcc-objc@6.

* gnu/packages/gcc.scm (gcc-objc@6): New variable.

gnu: Add gcc-objc++@5.

* gnu/packages/gcc.scm (gcc-objc++@5): New variable.

gnu: Add gcc-objc@5.

* gnu/packages/gcc.scm (gcc-obj@5): New variable.

guix download: Honor mirrors when using '-o'.

Previously "guix download -o x mirror://gnu/…" would fail.

* guix/scripts/download.scm (download-to-file): Pass #:mirrors to
'url-fetch'.

gnu: graphicsmagick: Fix CVE-2017-{11403,14103}.

* gnu/packages/imagemagick.scm (graphicsmagick)[source]: Add patch.
* gnu/packages/patches/graphicsmagick-CVE-2017-11403+CVE-2017-14103.patch:
New file.
* gnu/local.mk (dist_patch_DATA): Register it.

gnu: Add cpputest.

* gnu/packages/check.scm (cpputest): New variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu: Add stgit.

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

Signed-off-by: Ludovic Courtès <ludo@gnu.org>