gnu: Fix incorrect references to %GNU-BUILD-SYSTEM-MODULES.

Fixes a regression introduced in 8ff3df5.

* gnu/packages/emacs.scm (emacs-w3m)[arguments]: Use quasiquote, not
  quote.
  (emacs-wget)[arguments]: Likewise, and use unquote-splicing for
  %GNU-BUILD-SYSTEM-MODULES.
  (emms): Likewise.
* gnu/packages/haskell.scm (ghc): Likewise.
* gnu/packages/samba.scm (samba): Likewise.

lint: Report patches that cannot be found.

* guix/scripts/lint.scm (check-patch-file-names): Wrap body in 'guard'.
* tests/lint.scm ("patches: not found"): New test.

lint: Rename 'check-patches' to 'check-patch-file-names'.

* guix/scripts/lint.scm (check-patches): Rename to...
  (check-patch-file-names): ... this.  Rename 'filename' to 'file'.
  (%checkers): Adjust accordingly.
* tests/lint.scm ("patches: file names"): Likewise.

gnu: curl: Update to 7.41.0.  Support CURLOPT_CAPATH on GnuTLS.

Fixes <http://bugs.gnu.org/20121>.

* gnu/packages/patches/curl-gss-api-fix.patch: Delete file.
* gnu/packages/patches/curl-support-capath-on-gnutls.patch,
  gnu/packages/patches/curl-support-capath-on-gnutls-conf.patch: New files.
* gnu-system.am (dist_patch_DATA): Add new patches and remove old one.
* gnu/packages/curl.scm (curl): Update to 7.41.0.  Add new patches and remove
  old one.  Disable one unit test.

Modified-By: Mark H Weaver <mhw@netris.org>

gnu: gnome-themes-standard: Update to 3.16.0.

This is a followup to 12f7f4a.

* gnu/packages/gnome.scm (gnome-themes-standard): Update hash.

gnu: python-2: Restore python-libffi-mips-n32-fix.patch.

This patch was removed in 08c045091e8d8da3b4c677540ed577e8f2448b0d,
but it's still needed for python-2.

* gnu/packages/patches/python-libffi-mips-n32-fix.patch: Restore it.
* gnu-system.am (dist_patch_DATA): Add it back.

python: Update to 3.4.3

* gnu/packages/python.scm (python): Update from 3.3.5 to 3.4.3.
* gnu/packages/patches/python-fix-tests.patch: Update the required test fixes.
* gnu/packages/patches/python-libffi-mips-n32-fix.patch: Remove it...
* gnu-system.am (dist_patch_DATA): ... and do not reference it here.

gnu: Add geocode-glib.

* gnu/packages/gnome.scm (geocode-glib): New variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu: gnome-desktop: Update to 3.16.0.

* gnu/packages/gnome.scm (gnome-desktop): Update to 3.16.0.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

Merge branch 'master' into core-updates

gnu: libtasn1: Update to 4.4 [fix for CVE-2015-2806].

* gnu/packages/gnutls.scm (libtasn1): Update to 4.4.

gnu: nettle: Update to 3.1.

* gnu/packages/nettle.scm (nettle): Update to 3.1.  Add 'arguments'
  field.

gnu: nettle: Make version 3 the default.

* gnu/packages/nettle.scm (nettle): Rename to...
  (nettle-2): ... this.
  (nettle-3): Rename to...
  (nettle): ... this.
* gnu/packages/gnutls.scm (gnutls): Use NETTLE-2.
* gnu/packages/lsh.scm (lsh): Likewise.

gnu: gcc: Do not pass -dynamic-linker to linker when !shared on arm.

Fixes <http://bugs.gnu.org/20102>.

* gnu/packages/patches/gcc-arm-link-spec-fix.patch: New file.
* gnu-system.am (dist_patch_DATA): Add it.
* gnu/packages/gcc.scm (gcc-4.8, gcc-4.9): Add patch.
* gnu/packages/cross-base.scm (cross-gcc): Preserve patches from gcc-4.8.

Co-Authored-By: Ludovic Courtès <ludo@gnu.org>

http-client: Add workaround for HTTP pipelining on Guile <= 2.0.9.

Reported by Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>.

* guix/http-client.scm (make-delimited-input-port): New procedure.
  Install it in (web response) for Guile <= 2.0.9.

activation: Remove undeclared user accounts and groups.

Fixes <http://bugs.gnu.org/19795>.
Reported by David Thompson <dthompson2@worcester.edu>.

* gnu/build/activation.scm (enumerate, current-users, current-groups,
  delete-user, delete-group): New procedures.
  (activate-users+groups): Add calls to 'delete-user' and
  'delete-group'.
* doc/guix.texi (User Accounts): Add a paragraph about statelessness.
  Explain that passwords are preserved.

gnu: Add ghc-http.

* gnu/packages/haskell.scm (ghc-http): New variable.

gnu: Add ghc-network-uri.

* gnu/packages/haskell.scm (ghc-network-uri): New variable.

gnu: Add ghc-network.

* gnu/packages/haskell.scm (ghc-network): New variable.

gnu: Add ghc-vector.

* gnu/packages/haskell.scm (ghc-vector): New variable.