gnu: Split (gnu packages base), adding (gnu packages commencement).

* gnu/packages/base.scm (gnu-make-boot0, diffutils-boot0,
  findutils-boot0, %boot0-inputs, nix-system->gnu-triplet, boot-triplet,
  binutils-boot0, gcc-boot0, perl-boot0, linux-libre-headers-boot0,
  texinfo-boot0, %boot1-inputs, glibc-final-with-bootstrap-bash,
  cross-gcc-wrapper, static-bash-for-glibc, glibc-final,
  gcc-boot0-wrapped, %boot2-inputs, binutils-final, libstdc++,
  gcc-final, ld-wrapper-boot3, %boot3-inputs, bash-final, %boot4-inputs,
  guile-final, gnu-make-final, ld-wrapper, coreutils-final, grep-final,
  %boot5-inputs, %final-inputs, canonical-package, gcc-toolchain,
  gcc-toolchain-4.8, gcc-toolchain-4.9): Move to...
* gnu/packages/commencement.scm: ... here.  New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.
* build-aux/check-final-inputs-self-contained.scm: Adjust accordingly.
* gnu/packages/cross-base.scm: Likewise.
* gnu/packages/make-bootstrap.scm: Likewise.
* guix/build-system/cmake.scm (cmake-build): Likewise.
* guix/build-system/gnu.scm (standard-packages, gnu-build,
  gnu-cross-build): Likewise.
* guix/build-system/perl.scm (perl-build): Likewise.
* guix/build-system/python.scm (python-build): Likewise.
* guix/build-system/trivial.scm (guile-for-build): Likewise.
* guix/download.scm (url-fetch): Likewise.
* guix/gexp.scm (default-guile): Likewise.
* guix/git-download.scm (git-fetch): Likewise.
* guix/monads.scm (run-with-store): Likewise.
* guix/packages.scm (default-guile): Likewise.
* guix/scripts/package.scm (guix-package): Likewise.
* guix/scripts/refresh.scm: Likewise.
* guix/svn-download.scm (svn-fetch): Likewise.
* tests/builders.scm (%bootstrap-inputs, %bootstrap-search-paths):
  Likewise.
* tests/packages.scm ("GNU Make, bootstrap"): Likewise.
* tests/guix-package.sh: Likewise.
* gnu/services/base.scm: Use 'canonical-package' instead of xxx-final.
* gnu/services/xorg.scm: Likewise.
* gnu/system/vm.scm: Likewise.
* guix/scripts/pull.scm (guix-pull): Likewise.

Merge branch 'core-updates'

system: Prefer packages from %FINAL-INPUTS.

* gnu/packages/base.scm (canonical-package): New procedure.
* gnu/system.scm (%base-packages): Pass BASH, COREUTILS, FINDUTILS,
  GREP, and SED through 'canonical-package'.

gnu: Remove dependency from gzip to the bootstrap binaries.

* gnu/packages/base.scm (grep-final): New variable.
  (%boot5-inputs): Add it.
  (%final-inputs): Use it.

gnu: grep: Upgrade to 2.20.

* gnu/packages/base.scm (grep): Upgrade to 2.20.

gnu: coreutils: Remove run-time dependency on Bash.

* gnu/packages/base.scm (coreutils)[arguments] <patch-shell-references>:
  Leave src/split.c unpatched.  Set $SHELL.  Use .../bin/sh and not
  .../bin/bash in tests.

gnu: gcc: Add a "lib" output.

* gnu/packages/gcc.scm (gcc-4.7)[configure-flags]: Add
  --with-gxx-include-dir.
  [outputs]: New field.
  [arguments] <phases>: Adjust to use the "lib" output.  Add
  'substitute*' calls for "libstdc++-v3/python/Makefile.in" and
  "gcc/config.in".
* gnu/packages/base.scm (gcc-boot0) <symlink-libgcc_eh>: Use the "lib"
  output.
  (cross-gcc-wrapper): Add 'outputs' field.
  (glibc-final)[arguments]: Adjust #:allowed-references to list
  '(GCC-BOOT0 "lib").
  (libstdc++): Add 'outputs' field.
  (gcc-final)[arguments]: Add "lib" to #:allowed-references.
* gnu/packages/make-bootstrap.scm (%gcc-static): Add 'outputs' field.

gnu: glibc-final: Remove top-level circular dependency.

This fixes a top-level circular dependency between linux.scm and
base.scm introduced in 2e92375.

* gnu/packages/base.scm (glibc-final): Remove call to
  'package-with-restricted-references', and use an 'arguments' field
  instead.

gnu: gcc-final: Make sure the output refers only to libc.

* gnu/packages/base.scm (gcc-final)[arguments]: Add
  #:allowed-references.

gnu: binutils-final: Make sure the output refers only to libc.

* gnu/packages/base.scm (binutils-final)[arguments]: Add
  #:allowed-references.

gnu: glibc-final: Make sure we hold just the right set of references.

* gnu/packages/base.scm (glibc-final): Wrap in
  'package-with-restricted-references'.

gnu: glibc: Make sure the bootstrap libc is not in $CPATH.

This fixes a bug whereby the bootstrap-glibc headers could be picked up
when building libc.so, which could be noticed by the fact that the
.debug files contained references to bootstrap-glibc.

* gnu/packages/base.scm (glibc-final-with-bootstrap-bash)[arguments]:
  Add 'pre-configure' phase.
  [inputs]: Remove 'alist-delete' call.

gnu: Build the final Coreutils before Findutils.

This fixes a bug whereby Findutils' 'updatedb' script would retain a
reference to the bootstrap binaries ('sort', etc.)

* gnu/packages/base.scm (coreutils-final, %boot5-inputs): New variables.
  (%final-inputs): Use them.

Merge branch 'master' into core-updates

gnu: Set proper source location for 'gcc-final'.

* gnu/packages/base.scm (gcc-final)[location]: New field.
  Reported by Andreas Enge <andreas@enge.fr>.

gnu: grep: Upgrade to 2.19.

* gnu/packages/base.scm (grep): Upgrade to 2.19.

Merge branch 'master' into core-updates

gnu: Add GCC 4.9.0.

* gnu/packages/gcc.scm (gcc-4.9): New variable.
* gnu/packages/base.scm (gcc-toolchain-4.9): New variable.

gnu: gmp: Upgrade to 6.0.0a.

* gnu/packages/multiprecision.scm (gmp): Upgrade to 6.0.0a.
* gnu/packages/base.scm (gcc-boot0): Modify symbolic link to point to
    gmp-6.0.0 instead of the non-existing gmp-6.0.0a.

gnu: gcc-final: Add Texinfo as an input.

* gnu/packages/base.scm (gcc-final)[native-inputs]: New field.