gnu: Add ruby-deep-merge.

* gnu/packages/ruby.scm (ruby-deep-merge): New public variable.

gnu: git-remote-gcrypt: Update to 1.3.

* gnu/packages/version-control.scm (git-remote-gcrypt): Update to 1.3.

news: Add ‘nl’ translation.

* etc/news.scm: Add an ‘nl’ ‘translation’.

news: Remove superfluous closing bracket.

* etc/news.scm: Use an equal number of ‘(’s and ‘)’s.

gnu: wmbattery: Update to 2.54.

* gnu/packages/gnustep.scm (wmbattery): Update to 2.54.
[native-inputs]: Remove autoconf & automake.

gnu: libmanette: Update to 0.2.4.

* gnu/packages/games.scm (libmanette): Update to 0.2.4.

gnu: translate-shell: Update to 0.9.6.12.

* gnu/packages/dictionaries.scm (translate-shell): Update to 0.9.6.12.

gnu: gnu-efi: Mark up description.

* gnu/packages/efi.scm (gnu-efi)[description]: Use @acronym.

gnu: gnu-efi: Update to 3.0.12.

* gnu/packages/efi.scm (gnu-efi): Update to 3.0.12.

gnu: http-parser: Fix build [and guix pull] on armhf-linux.

* gnu/packages/web.scm (http-parser)[source]: Add patch.
* gnu/packages/patches/http-parser-fix-assertion-on-armhf.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.

gnu: mame: Update to 0.221.

* gnu/packages/emulators.scm (mame): Update to 0.221.

gnu: python-lmdb: Remove Python 2 variant.

* gnu/packages/databases.scm (python2-lmdb): Remove variable.

gnu: python-lmdb: Update to 0.98.

* gnu/packages/databases.scm (python-lmdb): Update to 0.98.

gnu: perl-dbd-sqlite: Update to 1.64.

* gnu/packages/databases.scm (perl-dbd-sqlite): Update to 1.64.

gnu: perl-dbi: Update to 1.643.

* gnu/packages/databases.scm (perl-dbi): Update to 1.643.

gnu: perl-db-file: Update to 1.853.

* gnu/packages/databases.scm (perl-db-file): Update to 1.853.

news: Add missing closing parentheses.

This broke 'guix pull'.  Apologies!

* etc/news.scm: Fix the latest entry.

news: Update copyright.

* etc/news.scm: Update copyright, as a follow-up to 489699c456.

news: Add entry for Btrfs subvolume boot support.

* etc/news.scm: Add entry.

bootloader: grub: Allow booting from a Btrfs subvolume.

* gnu/bootloader/grub.scm (strip-mount-point): Remove procedure.
(normalize-file): Add procedure.
(grub-configuration-file): New BTRFS-SUBVOLUME-FILE-NAME parameter.  When
defined, prepend its value to the kernel and initrd file names, using the
NORMALIZE-FILE procedure.  Adjust the call to EYE-CANDY to pass the
BTRFS-SUBVOLUME-FILE-NAME argument.  Normalize the KEYMAP file as well.
(eye-candy): Add a BTRFS-SUBVOLUME-FILE-NAME parameter, and use it, along with
the NORMALIZE-FILE procedure, to normalize the FONT-FILE and IMAGE nested
variables.  Adjust doc.
* gnu/bootloader/depthcharge.scm (depthcharge-configuration-file): Adapt.
* gnu/bootloader/extlinux.scm (extlinux-configuration-file): Likewise.
* gnu/system/file-systems.scm (btrfs-subvolume?)
(btrfs-store-subvolume-file-name): New procedures.
* gnu/system.scm (operating-system-bootcfg): Specify the Btrfs
subvolume file name the store resides on to the
`operating-system-bootcfg' procedure, using the new
BTRFS-SUBVOLUME-FILE-NAME argument.
* doc/guix.texi (File Systems): Add a Btrfs subsection to document the use of
subvolumes.
* gnu/tests/install.scm (%btrfs-root-on-subvolume-os)
(%btrfs-root-on-subvolume-os-source)
(%btrfs-root-on-subvolume-installation-script)
(%test-btrfs-root-on-subvolume-os): New variables.