distro: Rename (distro) to (gnu packages).

* distro.scm: Rename to...
* gnu/packages.scm: ... this.  Update all users accordingly.
* Makefile.am (MODULES): Adjust accordingly.
* po/POTFILES.in: Likewise.

distro: Change the module name space to (gnu ...).

* distro: Rename to...
* gnu: ... this.  Update module names accordingly.
* Makefile.am: Adjust accordingly.
* po/POTFILES.in: Likewise.
* distro.scm: Search for files under /gnu/packages instead of
  /distro/packages.
* gnu/packages/base.scm (ld-wrapper-boot3): Likewise.

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

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'.

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: Go for one module per package.

The alternative, which was to use one module per category, would
probably not scale well.  First, because many packages could fall into
several categories (does GnuTLS go into "networking", "security", or
"libraries"?).  Second, because that could easily lead to circular
dependencies among modules ("security" and "networking" depend on each
other, etc.)

* distro/packages/databases.scm: Rename to...
* distro/packages/recutils.scm: ... this.
* distro/packages/typesetting.scm: Rename to...
* distro/packages/lout.scm: ... this.
* Makefile.am (MODULES): Adjust accordingly.
* po/POTFILES.in: Likewise.

packages: `description' → `synopsis', `long-description' → `description'.

* guix/packages.scm (<package>): Rename `description' to `synopsis', and
  `long-description' to `description'.
* tests/packages.scm, distro/packages/base.scm,
  distro/packages/databases.scm, distro/packages/guile.scm,
  distro/packages/typesetting.scm:  Update accordingly.
* po/Makevars (XGETTEXT_OPTIONS): Update `--keyword' flags accordingly.

Add (guix ui).

* guix/ui.scm: New file.
* Makefile.am (MODULES): Add it.
* po/POTFILES.in: Add it.

* guix-build.in: Use it.
  (_, N_, leave): Remove.
  (guix-build): Use `with-error-handling' instead of the `guard' form.
* guix-download.in: Use it.
  (_, N_, leave): Remove.

Add `guix-download'.

* guix-download.in: New file.
* configure.ac: Emit `guix-download' and make it executable.
* Makefile.am (bin_SCRIPTS): Add `guix-download'.
* po/POTFILES.in: Add `guix-download.in'.

Fix and update `POTFILES.in'.

* po/POTFILES.in: Update.

build: Tell xgettext that the source is UTF-8.

* po/Makevars (XGETTEXT_OPTIONS): Add `--from-code=UTF-8'.

Add `guix-build'.

* guix-build.in: New file.

* configure.ac: Emit `guix-build'.  Add `commands-exec'.
* Makefile.am (bin_SCRIPTS): New variable.
* po/POTFILES.in: Add `guix-build.in'.

Add (distro) with a package searching facility.

* Makefile.am (MODULES): Add `distro.scm'.

* distro.scm: New file.
* po/POTFILES.in: Add it.

* tests/packages.scm ("find-packages-by-name", "find-packages-by-name
  with version"): New tests.

Gettextize, with GNU Gettext 0.18.1.

* Makefile.am (EXTRA_DIST): Add `build-aux/config.rpath'.
  (SUBDIRS, ACLOCAL_AMFLAGS): New variables.

* configure.ac: Use `AM_GNU_GETTEXT'.  Emit `po/Makefile.in'.

* po/Makevars, po/POTFILES.in: New files.