gnu: rcs: Update to 5.9.3.

* gnu/packages/version-control.scm (rcs): Update to 5.9.3.
gnu: libidn: Update to 1.29.

* gnu/packages/libidn.scm (libidn): Update to 1.29.
gnu: parallel: Update to 20140922.

* gnu/packages/parallel.scm (parallel): Update to 20140922.
gnu: gcl: Update to 2.6.11.

* gnu/packages/lisp.scm (gcl): Update to 2.6.11.
gnu: help2man: Update to 1.46.3.

* gnu/packages/man.scm (help2man): Update to 1.46.3.
gnu: libxscrnsaver: Propagate input scrnsaverproto.

* gnu/packages/xorg.scm (libxscrnsaver): Propagate input scrnsaverproto,
    since scrnsaver.h from libxscrnsaver includes saver.h from scrnsaverproto.
gnu: mit-scheme: Update to 9.2.

* gnu/packages/scheme.scm (mit-scheme): Update to 9.2.
build: Don't generate Emacs autoloads when Emacs is unavailable.

Reported by Andreas Enge.

* configure.ac: Define 'HAVE_EMACS' Automake conditional.
* emacs.am ($(AUTOLOADS)): Wrap in 'if HAVE_EMACS'.
build: Don't install elisp files when Emacs is unavailable.

* emacs.am (dist_lisp_DATA, nodist_lisp_DATA): Wrap in 'if HAVE_EMACS'.
gnu: phonon: Update to 4.8.0.

* gnu/packages/kde.scm (phonon): Update to 4.8.0.
gnu: mit-scheme: Fix source file name for mips64el.

* gnu/packages/scheme.scm (mit-scheme): Fix source file name for
     architectures other than x86_64 and i686.
gnu: mit-scheme: Delete more dangling symlinks for non-x86 systems.

* gnu/packages/scheme.scm (mit-scheme): Delete more dangling symlinks for
    non-x86 systems.
gnu: Add graphite2.

* gnu/packages/fontutils.scm (graphite2): New variable.
gnu: mit-scheme: Rename top-level helper.

Suggested by Mark H. Weaver.

* gnu/packages/scheme.scm (source-directory): Rename to...
  (mit-scheme-source-directory): ... this.
gnu: Add perl-dbi and perl-dbd-sqlite.

* gnu/packages/databases.scm (perl-dbi, perl-dbd-sqlite): New variable.
gnu: Add perl-www-curl.

* gnu/packages/web.scm (perl-www-curl): New variable.
gnu: Add Nix.

This commit is dedicated to the Nix project, without which we wouldn't
be hacking all this today.  :-)

* gnu/packages/package-management.scm (nix): New variable.
gnu: qt-4: Explicitly link with icu.

* gnu/packages/qt.scm (qt-4): Explicitly link with libicui18n, which is
    dlopened by QtCore.so.
gnu: hurd-headers: Use --build instead of --host.

* gnu/packages/hurd.scm (hurd-headers): Replace '--host' with
  '--build'.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>
gnu: base: Add glibc-hurd and hurd-minimal.

Reinstates commit bc046a94, among other things.

* gnu/packages/base.scm (glibc/hurd, glibc/hurd-headers): New variables.
* gnu/packages/hurd.scm (hurd-minimal): New variable.
* gnu/packages/patches/glibc-make-4.0.patch: New file.
* gnu/packages/patches/glibc-hurd-extern-inline.patch: New file.
* gnu/packages/patches/libpthread-glibc-preparation.patch: New file.
* gnu/packages/patches/hurd-minimal.patch: New file.
* gnu-system.am (dist_patch_DATA): Add them.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>