doc: Document the features and `guix-package'.

* doc/guix.texi: Change the category to "Package management".  Add an
  @direntry for "Invoking guix-package".
  (Package Management): New chapter.

guix-package: Fix handling of the PACKAGE:OUTPUT syntax.

* guix-package.in (guix-package)[find-package]: Return the correct NAME
  and SUB-DRV when NAME contains #\:.

* tests/guix-package.sh (profile): Add test.

guix-package: Fix invalid module use.

* guix-package.in: Use (distro packages guile), not (... base).

build: Remove now unnecessary dependency of downloads on guix/utils.go.

* Makefile.am (distro/packages/bootstrap/x86_64-linux/guile-bootstrap-2.0.6.tar.xz,
  distro/packages/bootstrap/i686-linux/guile-bootstrap-2.0.6.tar.xz):
  Remove dependency on guix/utils.go.

doc: Document `guix-build'.

* doc/guix.texi (Invoking guix-build): Populate.

doc: Remove unnecessary @ifinfo.

* doc/guix.texi: Remove @ifinfo around @dir{category,entry}.  Suggested
  by Karl Berry <karl@freefriends.org>.

distro: Move bootstrap tarball packages to (distro packages make-bootstrap).

* distro/packages/base.scm (binutils-final): Make public.
  (static-package, %bash-static, %static-inputs, %static-binaries,
  %binutils-static, %binutils-static-stripped, %glibc-stripped,
  %gcc-static, %gcc-stripped, %guile-static, %guile-static-stripped,
  tarball-package, %bootstrap-binaries-tarball,
  %binutils-bootstrap-tarball, %glibc-bootstrap-tarball,
  %guile-bootstrap-tarball): Move to...
* distro/packages/make-bootstrap.scm: ... here.  New file.
* Makefile.am (MODULES): Add it.

distro: bash-final: Link with `-static-libgcc'.

* distro/packages/base.scm (bash-final): Pass through
  `static-libgcc-package'.

build-system/gnu: Add `static-libgcc-package' & supporting procedure.

* guix/build-system/gnu.scm (package-with-extra-configure-variable,
  static-libgcc-package): New procedures.

distro: gcc: Don't add a RUNPATH to GCC when using `-static-libgcc'.

* distro/packages/base.scm (gcc-4.7)[LIB_SPEC]: Add a `-rpath' to GCC
  only when !static and !static-libgcc.

distro: readline: Allow stripping of the libraires.

* distro/packages/readline.scm (readline)[arguments]: Add `post-install'
  phase to make libraries writable.

utils: Add `default-keyword-arguments' and `substitute-keyword-arguments'.

* distro/packages/base.scm (default-keyword-arguments,
  substitute-keyword-arguments): Move to...
* guix/utils.scm: ... here.

distro: Add missing `package-with-bootstrap-guile'.

* distro/packages/base.scm (binutils-final): Add missing
  `package-with-bootstrap-guile'.

distro: recutils: Comment out optional dependencies.

* distro/packages/recutils.scm (recutils): Comment out optional
  dependencies not packaged here.

distro: Add GnuPG and companion libraries.

* distro/packages/gnupg.scm: New file.
* Makefile.am (MODULES): Add it.

distro: Add zlib.

* distro/packages/compression.scm (zlib): New variable.

distro: Add (distro packages compression).

* distro/packages/base.scm (gzip, bzip2, xz): Move to...
* distro/packages/compression.scm: ... here.  New file.
* Makefile.am (MODULES): Add it.

distro: Add GNU Pth.

* distro/packages/pth.scm: New file.
* Makefile.am (MODULES): Add it.

distro: Add GNU gperf.

* distro/packages/gperf.scm: New file.
* Makefile.am (MODULES): Add it.
* distro/packages/guile.scm (guile-reader): Use it.

distro: Split (distro packages base) into several files.

* distro/packages/base.scm (libsigsegv, gawk, perl, m4, gmp, mpfr, mpc,
  ncurses, readline, bash, libtool, libunistring, libffi, pkg-config,
  libgc): Move to modules of their own.
  (guile-1.8, guile-2.0): Move to...
* distro/packages/guile.scm: ... here.

* distro/packages/bash.scm, distro/packages/bdw-gc.scm,
  distro/packages/gawk.scm, distro/packages/libffi.scm,
  distro/packages/libsigsegv.scm, distro/packages/libtool.scm,
  distro/packages/libunistring.scm, distro/packages/m4.scm,
  distro/packages/multiprecision.scm, distro/packages/ncurses.scm,
  distro/packages/perl.scm, distro/packages/pkg-config.scm,
  distro/packages/readline.scm: New files.