gnu: zstd: Update to 1.2.0.

* gnu/packages/compression.scm (zstd): Update to 1.2.0.

gnu: abiword: Update to 3.0.2.

* gnu/packages/patches/abiword-explictly-cast-bools.patch: Update patch.
* gnu/packages/patches/abiword-black-drawing-with-gtk322.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/abiword.scm (abiword): Update to 3.0.2.
[source]: Remove outdated snippet; add new patch.
[arguments]: Pass CXXFLAGS.

gnu: jalv-select: Fix regular expression.

* gnu/packages/music.scm (jalv-select)[arguments]: Fix substitution to find
the available jalv executables.

gnu: gxtuner: Update to 2.4.

* gnu/packages/music.scm (gxtuner): Update to 2.4.
[inputs]: Replace gtk+-2 with gtk+.

gnu: jalv-select: Update to 0.8.

* gnu/packages/music.scm (jalv-select): Update to 0.8.

gnu: qsynth: Update to 0.4.4.

* gnu/packages/audio.scm (qsynth): Update to 0.4.4.

gnu: qjackctl: Build with JACK 1.

We build all packages with JACK 1.  It is compatible with JACK 2, which users
may install to get additional features.

* gnu/packages/audio.scm (qjackctl)[inputs]: Replace "jack-2" with "jack-1".

gnu: qjackctl: Update to 0.4.5.

* gnu/packages/audio.scm (qjackctl): Update to 0.4.5.

gnu: samplv1: Update to 0.8.2.

* gnu/packages/music.scm (samplv1): Update to 0.8.2.

gnu: drumkv1: Update to 0.8.2.

* gnu/packages/music.scm (drumkv1): Update to 0.8.2.

gnu: synthv1: Update to 0.8.2.

* gnu/packages/music.scm (synthv1): Update to 0.8.2.

gnu: linux-libre@4.9: Update to 4.9.26.

* gnu/packages/linux.scm (linux-libre-4.9): Update to 4.9.26.

gnu: linux-libre@4.4: Update to 4.4.66.

* gnu/packages/linux.scm (linux-libre-4.4): Update to 4.4.66.

gnu: Add cool-retro-term.

* gnu/packages/terminals.scm (cool-retro-term): New variable.
* gnu/packages/patches/cool-retro-term-remove-non-free-fonts.patch,
gnu/packages/patches/cool-retro-term-fix-array-size.patch,
gnu/packages/patches/cool-retro-term-memory-leak-1.patch,
gnu/packages/patches/cool-retro-term-remove-non-free-fonts.patch: New patches.
* gnu/local.mk (dist_patch_DATA): Add them.

Co-authored-by: Eric Bavier <bavier@member.fsf.org>

gnu: openssh: groff is a native-input.

* gnu/packages/ssh.scm (openssh)[inputs]: Move groff ...
[native-inputs]: ... here.

gnu: guix: The variable for the last release is now 'guix-release'.

* gnu/packages/package-management.scm (guix-0.12.0): Rename to...
(guix-release): ... this.  Adjust users.

build: Use Gnulib's 'git-version-gen'.

* Makefile.am (EXTRA_DIST, BUILT_SOURCES): Add $(top_srcdir)/.version.
($(top_srcdir)/.version, gen-tarball-version): New targets.
(dist-hook): Depend on 'gen-tarball-version'.
(.PHONY): Add 'gen-tarball-version'.
* build-aux/git-version-gen: New file, from Gnulib v0.1-1312-ga87d5e5c6.
* configure.ac: Use it in 'AC_INIT'.  Use 'https' for the URL.

build: Remove 'sync-descriptions' target.

This target predates 'guix lint'.  Nowadays it makes little sense to run
it upon 'make dist'.

* Makefile.am (sync-descriptions): Remove.
(dist-hook, .PHONY): Remove reference to 'sync-descriptions'.

dir-locals.el: Add 'modify-phases' keywords.

* .dir-locals.el: Add indentation rules for 'replace', 'add-before' and
'add-after'.

etc: indent-code.el: Define source tree by "indent-code.el".

* etc/indent-code.el.in: Set default directory by "indent-code.el"
itself, otherwise it works only when called from the top directory of
the guix source tree.