Merge branch 'core-updates'

Conflicts:
	guix/build/union.scm

Merge branch 'master' into core-updates

Conflicts:
	build-aux/download.scm
	distro/packages/autotools.scm
	distro/packages/base.scm
	distro/packages/bootstrap.scm
	distro/packages/lsh.scm
	distro/packages/make-bootstrap.scm
	distro/packages/ncurses.scm
	distro/packages/perl.scm
	tests/derivations.scm
	tests/union.scm

Update license headers.

Change all license headers, except guix/build/* and ld-wrapper.scm, with
this code:

  (use-modules (guix build utils)
	       (srfi srfi-1))

  (fluid-set! %default-port-encoding "UTF-8")

  (substitute* (remove (lambda (f)
			 (or (string-contains f ".tar.")
			     (string-contains f ".git/")
			     (string-contains f ".so")
			     (string-suffix? ".o" f)
			     (string-suffix? ".a" f)
			     (string-suffix? ".go" f)
			     (string-suffix? ".pdf" f)
			     (string-suffix? ".png" f)
			     (string-suffix? ".info" f)
			     (equal? (basename f) "guix-daemon")
			     (equal? (basename f) "nix-setuid-helper")
			     (string-contains f "nix-upstream/")
			     (string-contains f "distro/packages/bootstrap/")))
		       (find-files "." "\\.[a-z]+$"))
    (("^([[:graph:]]+) This file is part of Guix." _ comment-start)
     (string-append comment-start " This file is part of GNU Guix."))
    (("^([[:graph:]]+) Guix --- Nix package management.*" _ comment-start)
     (string-append comment-start
		    " GNU Guix --- Functional package management for GNU\n"))
    (("^([[:graph:]]+) Guix is " _ comment-start)
     (string-append comment-start " GNU Guix is "))
    (("^([[:graph:]]+) along with Guix." _ comment-start)
     (string-append comment-start " along with GNU Guix."))
    (("^([[:graph:]]+) Copyright \\(C\\)" _ comment-start)
     (string-append comment-start " Copyright ©")))

Change headers using C-style comments manually.

release.nix: Update to new bootstrap Guile tarball.

* release.nix (bootstrap_guile): Update URLs and SHA256.
  (build)[preBuild]: Adjust tarball name.

Merge branch 'master' into core-updates

Conflicts:
	distro/packages/multiprecision.scm

release.nix: Remove trailing "/nix" from localstatedir.

* release.nix (tarball, build): Use /nix/var as localstatedir, as a
  follow-up to 7f4f065.

release.nix: tarball: Fix typo.

* release.nix (tarball): Replace "gnulib" by "nix".

release.nix: tarball: Fix typo.

* release.nix (tarball): Replace "gnulib" by "nix".

Merge branch 'nix-integration'

Conflicts:
	tests/guix-package.sh

release.nix: Add `build_disable_daemon'.

* release.nix (build_disable_daemon): New job.

release.nix: build: Allow builds within a chroot.

* release.nix (build): Remove `__noChroot' and `preConfigure'.

release.nix: Build the daemon.

* release.nix (tarball): Add `preAutoconf'.  Augment `buildInputs' and
  `configureFlags' to allow daemon builds.
  (build): Likewise.

release.nix: Pass `--with-libgcrypt-prefix' in the `tarball' job.

* release.nix (jobs.tarball)[configureFlags]: Pass
  `--with-libgcrypt-prefix'.

build: Clearly mark Nixpkgs as optional.

* configure.ac: Always show the result of checking for Nixpkgs.  Don't
  warn when Nixpkgs is not found.
* Makefile.am (AM_DISTCHECK_CONFIGURE_FLAGS): Remove `--with-nixpkgs'
  flag.
* guix/utils.scm (%nixpkgs-directory): Use either the compile-time or
  the run-time `NIXPKGS' environment variable.
* release.nix (jobs.tarball, jobs.build): Remove `--with-nixpkgs'
  configure flag.
* README: Mark Nixpkgs as optional.

* distro/packages/databases.scm, distro/packages/guile.scm,
  distro/packages/typesetting.scm: Change uses of `nixpkgs-derivation*'
  to `nixpkgs-derivation', to avoid failing at compile-time.

release.nix: Use `--no-substitutes' in `distro.hello'.

* release.nix (distro.hello): Use `guix-build --no-substitutes', to
  avoid failures due to unavailable stale substitutes on
  hydra.nixos.org.

release.nix: Change `distro.hello' to produce something.

* release.nix (distro.hello)[buildPhase]: Tee the log to $out.  Add a
  `name' attribute; remove `buildInputs' and instead use the full path
  to `guix-build'.

release.nix: Add a `distro.hello' job.

* release.nix (distro.hello): New job.

release.nix: Pre-download the Guile bootstrap tarball.

* release.nix (bootstrap_guile): New variable.
  (build)[preBuild]: New attribute.

release.nix: Set succeed-on-failure and build-out-source-tree.

* release.nix: Define `succeedOnFailure', `keepBuildDirectory', and
  `buildOutOfSourceTree'.
  (build): Inherit them.

release.nix: Add dependency on GNU Texinfo.

* release.nix (tarball)[buildNativeInputs]: Add `texinfo'.