ui: Don't make substituter-related RPCs at all when substitutes are disabled.

Reported by Nikita Karetnikov and Cyril Roelandt.

* guix/ui.scm (show-what-to-build): Call `substitutable-path-info'
  only when USE-SUBSTITUTES? is true.

gnu: Add GNU vc-dwim.

* gnu/packages/version-control.scm (vc-dwim): New variable.

gnu: Add GNU Rush.

* gnu/packages/rush.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.

substitute-binary: Avoid dangling connections to the server.

* guix/web.scm (open-socket-for-uri): New procedure.
  (http-fetch): Add `port' keyword parameter; use it.
* guix/scripts/substitute-binary.scm (%random-state): New variable.
  (with-timeout): Wait a little before retrying.
  (fetch): Use `open-socket-for-uri', and keep a copy of the socket in
  variable `port'.  Close PORT upon timeout.

gnutls: fix the test-suite for 32 bits systems.

* gnu/packages/patches/gnutls-fix-tests-on-32-bits-system.patch: New file.
* gnu-system.am: Add it here...
* gnu/packages/gnutls.scm (gnutls): ... and use it here.

Thanks to Nikos Mavrogiannopoulos for providing this patch:
http://permalink.gmane.org/gmane.comp.encryption.gpg.gnutls.devel/6778

gnu: lout: Upgrade to 3.40.

* gnu/packages/lout.scm (lout): Upgrade to 3.40.

download: Add Savannah's master site.

* guix/download.scm (%mirrors): Add the "-noredirect" version of
  Savannah.

gnu: lsh: Upgrade to 2.1.

* gnu/packages/lsh.scm (lsh): Upgrade to 2.1.  Add Nettle as an input.
  Remove now unneeded patches.
* gnu/packages/patches/lsh-guile-compat.patch,
  gnu/packages/patches/lsh-no-root-login.patch,
  gnu/packages/patches/lsh-pam-service-name.patch: Remove.
* gnu-system.am (dist_patch_DATA): Remove them.

gnu: bigloo: Explicitly link libbigloopthread against libgc.

* gnu/packages/scheme.scm (bigloo): In `configure' phase, change
  api/thread/src/Makefile to explicitly link against libgc.

gnu: Add gdk-pixbuf.

* gnu/packages/gtk.scm (gdk-pixbuf): New variable.

gnu: ed: Upgrade to 1.9.

* gnu/packages/ed.scm (ed): Upgrade to 1.9.

gnu: gcc-4.8: Upgrade to 4.8.1.

* gnu/packages/gcc.scm (gcc-4.8): Upgrade to 4.8.1.

download: Don't fail when abbreviating `file://' URIs.

* guix/build/download.scm (uri-abbreviation)[elide-path]: Handle the
  case where URI has no `host' part.

build: Move Hydra recipe to build-aux/hydra.

* hydra.scm: Rename to...
* build-aux/hydra/gnu-system.scm: ... this.
* Makefile.am (EXTRA_DIST): Adjust accordingly.

package: Fix i18n of the number of packages message.

* guix/scripts/package.scm (guix-package)[process-actions]: Use `N_' for
  i18n of the number of packages message.

substitute-binary: Report progress while downloading.

* guix/scripts/substitute-binary.scm (decompressed-port): Improve docstring.
  (progress-report-port): New procedure.
  (guix-substitute-binary)["--substitute"]: Use it to report progress.
* guix/build/download.scm: Export `progress-proc' and `uri-abbreviation'.

Update eo.po.

build: Split Makefile.am into two parts.

* Makefile.am (MODULES): Move gnu/* to gnu-system.am.
  (patchdir, dist_patch_DATA, bootstrapdir,
  bootstrap_x86_64_linuxdir, bootstrap_i686_linuxdir,
  dist_bootstrap_x86_64_linux_DATA, dist_bootstrap_i686_linux_DATA,
  nodist_bootstrap_x86_64_linux_DATA, nodist_bootstrap_i686_linux_DATA,
  install-data-hook, DISTCLEANFILES, DOWNLOAD_FILE,
  gnu/packages/bootstrap/x86_64-linux/guile-2.0.7.tar.xz,
  gnu/packages/bootstrap/i686-linux/guile-2.0.7.tar.xz): Move to...
* gnu-system.am: ... here.  New file.

package: Display the number of installed packages upon completion.

* guix/scripts/package.scm (guix-package)[process-actions]: Display the
  number of packages in the profile upon completion.

Add `substitute-binary.scm' to POTFILES.in.

* po/POTFILES.in: Add guix/scripts/substitute-binary.scm.