download: Report the progress of HTTP downloads.

* guix/build/download.scm (http-fetch): Rename `bv' to `bv-or-port'.
  Use `http-get*' followed by `dump-port' when the former is available,
  and pass a progress procedure to `dump-port'.

download: Report the progress of FTP downloads.

* guix/build/download.scm (progress-proc): New procedure.
  (ftp-fetch): Call `ftp-size' on URI.  Use `progress-proc', and pass
  the result to `dump-port', along with #:buffer-size.

ftp-client: Add `ftp-size'.

* guix/ftp-client.scm (ftp-size): New procedure.

distro: time: Adjust `configure' phase to old `configure' script.

* distro/packages/time.scm (time): Add `arguments'.

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

distro: Update bootstrap binaries to an nscd-less libc.

Update bootstrap binaries following changes in commit d3b5972 ("Build
glibc without nscd, and with static NSS modules.")

* Makefile.am (distro/packages/bootstrap/x86_64-linux/guile-2.0.7.tar.xz,
  distro/packages/bootstrap/i686-linux/guile-2.0.7.tar.xz): Update hashes.
* build-aux/download.scm (file-name->uri): Update URL.
* distro/packages/bootstrap.scm (%bootstrap-coreutils&co,
  %bootstrap-binutils, %bootstrap-glibc, %bootstrap-gcc): Update URLs
  and hashes.

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.

Add `guix-gc'.

* guix-gc.in, tests/guix-gc.sh: New files.
* configure.ac: Output `guix-gc', and make it executable.
* Makefile.am (bin_SCRIPTS): Add `guix-gc'.
  (TESTS): Add `tests/guix-gc.sh'.
* doc/guix.texi (Features): Add xref to "Invoking guix-gc".
  (Invoking guix-gc): New node.
* po/POTFILES.in: Add `guix-gc.in'.

guix-build: Make `--root' effective for .drv files too.

* guix-build.in (guix-build)[register-root]: Change first argument to
  `paths', which should be a list of store paths.  Update caller to call
  `derivation-path->output-paths' on DRV.  When `derivations-only?',
  also register root for .drv files.

derivations: Add `derivation-path->output-paths'.

* guix/derivations.scm (derivation-path->output-paths): New procedure.
* tests/derivations.scm ("multiple-output derivation"): Test it.

Update license headers of builder-side code.

Change license headers with this script:

  (use-modules (guix build utils))

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

  (substitute* (cons "distro/packages/ld-wrapper.scm"
		     (find-files "guix/build" "\\.scm$"))
    (("^([[: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 ©")))

* distro/packages/ld-wrapper.scm, guix/build/download.scm,
  guix/build/gnu-build-system.scm, guix/build/union.scm,
  guix/build/utils.scm: Update license headers.

utils: Add `which'.

* guix/build/utils.scm (which): New procedure.

* distro/packages/lsh.scm (lsh): Use `which' instead of `search-path'.
* distro/packages/perl.scm (perl): Likewise.
* distro/packages/attr.scm (attr): Likewise.

ui: Factorize bug-report information in `--help'.

* guix/config.scm.in (%guix-home-page-url): New variable.
* guix/ui.scm (show-bug-report-information): New procedure.
* guix-build.in (show-help): Use it.
* guix-download.in (show-help): Likewise.
* guix-import.in (show-help): Likewise.
* guix-package.in (show-help): Likewise.

distro: make-bootstrap: Add `%bootstrap-tarballs' package.

* distro/packages/make-bootstrap.scm (%bootstrap-tarballs): New
  variable.

distro: make-bootstrap: Build glibc without nscd, and with static NSS modules.

* distro/packages/make-bootstrap.scm (%glibc-with-relocatable-system):
  Rename to...
  (%glibc-for-bootstrap): ... this.  Add new configure flags.

distro: make-bootstrap: Make the Coreutils smaller.

* distro/packages/make-bootstrap.scm (%static-inputs)[coreutils]: Remove
  optional dependencies, except Perl; build with "-Os -g0"; disable
  tests.

distro: make-bootstrap: Fix arguments to gawk.

* distro/packages/make-bootstrap.scm (%static-inputs)[gawk]: Use
  `substitute-keyword-arguments' to preserve the #:phases argument of
  GAWK.

distro: libtool: Add a "bin" output.

* distro/packages/autotools.scm (libtool): Add a "bin" output.
* distro/packages/base.scm (guile-final): Remove comment about retained
  dependency.

distro: ncurses: Don't retain a reference to the bootstrap Bash.

* distro/packages/ncurses.scm (ncurses): Remove #:patch-shebangs?
  argument since it now has no effect.  Simplify PATCH-MAKEFILE-PHASE.
  Add `configure-phase', and use it.

distro: coreutils: Enable tests; add dependency on ACL and GMP.

* distro/packages/base.scm (coreutils): Set #:parallel-build? #f.  Add
  `patch-shell-references' phase.  Add 'acl', 'gmp', and 'perl' as
  inputs, as suggested by Nikita Karetnikov.