gnu: wdiff: Upgrade to 1.2.2.

* gnu/packages/wdiff.scm (wdiff): Upgrade to 1.2.2.

gnu: gawk: Revert previous commit, which should go into core-updates.

* gnu/packages/gawk.scm (gawk): Downgrade to 4.1.0 to avoid recompiling
    almost everything in master.

gnu: gawk: Upgrade to 4.1.1.

* gnu/packages/gawk.scm (gawk): Upgrade to 4.1.1.

linux-initrd: Mount / as a unionfs when asking for a volatile root.

* guix/build/linux-initrd.scm (make-essential-device-nodes): Make
  /dev/fuse.
  (boot-system): Add #:unionfs parameter.  Invoke UNIONFS instead of
  copying files over when VOLATILE-ROOT? is true.
* gnu/system/linux-initrd.scm (expression->initrd): Add #:inputs
  parameter.
  [files-to-copy]: New procedure.
  [builder]: Add 'to-copy' parameter; honor it.
  (qemu-initrd)[linux-modules]: Add 'fuse.ko' when VOLATILE-ROOT?.
  Pass UNIONFS-FUSE/STATIC as #:inputs; change builder to pass #:unionfs
  to 'boot-system'.

gnu: unionfs-fuse-static: Remove dependency on util-linux.

* gnu/packages/linux.scm (fuse-static): New variable.
  (unionfs-fuse/static): Use it.

gnu: man-pages: Fix URL.

* gnu/packages/man.scm (man-pages): Use the 'kernel.org' mirror set.

gnu: Add Linux man-pages.

* gnu/packages/man.scm (man-pages): New variable.

openssh: Add another mirror.

* gnu/packages/ssh.scm (openssh): Add the mirror.

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

gnu: Add Mosh.

* gnu/packages/ssh.scm (mosh): New variable.

gnu: Add perl-io-tty.

* gnu/packages/perl.scm (perl-io-tty): New variable.

gnu: Add Protobuf.

* gnu/packages/protobuf.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.

vm: Move image creation to (guix build vm); split into several procedures.

* guix/build/vm.scm (read-reference-graph, initialize-partition-table,
  install-grub, populate-store, evaluate-populate-directive,
  reset-timestamps, initialize-hard-disk): New procedures.
* gnu/system/vm.scm (qemu-image): Change 'builder' to a call to
  'initialize-hard-disk'.

vm: 'expression->derivation-in-linux-vm' can import modules in the VM.

* gnu/system/vm.scm (%imported-modules): New procedure.
  (expression->derivation-in-linux-vm): Add #:imported-modules
  parameter; remove #:modules.  Add LOADER, and change BUILDER to load
  it.
  (qemu-image): Remove useless #:modules argument.

vm: Strip import list.

* gnu/system/vm.scm: Strip #:select for (gnu packages base).

vm: Factorize input conversion.

* gnu/system/vm.scm (input->name+output): New procedure.
  (expression->derivation-in-linux-vm): Use it for 'input-alist'.
  (qemu-image)[input->name+derivation]: Remove.  Use
  'input->name+output' instead.

vm: Add (guix build vm) module.

* guix/build/vm.scm: New file.
* Makefile.am (MODULES): Add it.
* gnu/system/vm.scm (expression->derivation-in-linux-vm): Use it.

gnu: ffmpeg: Upgrade to 2.2.1.

* gnu/packages/video.scm (ffmpeg): Upgrade to 2.2.1.

gnu: qemu: Remove 'qemu-with-multiple-smb-shares' package.

* gnu/packages/qemu.scm (qemu/smb-shares): Remove.
* gnu/packages/patches/qemu-multiple-smb-shares.patch: Remove.
* gnu-system.am (dist_patch_DATA): Adjust accordingly.

vm: Use QEMU's para-virtualized file system support for all VMs.

* gnu/system/vm.scm (system-qemu-image/shared-store-script): Change
  #:qemu to default to QEMU.  Change INITRD to use a 9p mount for the
  store.  Change command-line to use -virtfs.

gnu: util-linux: Enable ddate.

* gnu/packages/linux.scm (util-linux): Add --enable-ddate configure flag.

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