gnu: xcursor-themes: Install data into package output directory.

* gnu/packages/xorg.scm (xcursor-themes): Install icons into output directory
    instead of libxcursor.

gnu: Add python2-pyicu.

* gnu/packages/python.scm (python2-pyicu): New variable.

gnu: Add python-simplejson, python2-simplejson.

* gnu/packages/python.scm (python-simplejson, python2-simplejson):
    New variables.

gnu: python2-pysqlite: Fix 'license'.

* gnu/packages/python.scm (python2-pysqlite): Refer to (@ (guix
  licenses) zlib), not to the same-named package.

gnu: Add GNU dmd.

* gnu/packages/system.scm (dmd): New variable.

gnu: dbus: Add dependency on libX11.

* gnu/packages/glib.scm: Use #:export instead of 'define-public'.
  (dbus): Add LIBX11 as an input.

Merge branch 'python'

gnu: gnutls: Upgrade to 3.2.4.

* gnu/packages/gnutls.scm (gnutls): Update to 3.2.4; remove 'arguments'
  field, remove "patch/fix-tests" from the inputs.
* gnu/packages/patches/gnutls-fix-tests-on-32-bits-system.patch: Remove.
* gnu-system.am (dist_patch_DATA): Adjust accordingly.

gnu: Add python2-mechanize.

* gnu/packages/python.scm (python2-mechanize): New variable.

gnu: Add python2-sqlite.

* gnu/packages/python.scm (python2-sqlite): New variable.

gnu: avahi, dbus: Use /var as $localstatedir.

* gnu/packages/avahi.scm (avahi): Pass '--localstatedir'; add
  'patch/localstatedir'.
* gnu/packages/glib.scm (dbus): Pass '--localstatedir' and
  '--with-session-socket-dir'; add 'patch/localstatedir'.
* gnu/packages/patches/avahi-localstatedir.patch,
  gnu/packages/patches/dbus-localstatedir.patch: New files.
* gnu-system.am (dist_patch_DATA): Add them.

gnu: Update python-babel, python2-babel to 1.3.

* gnu/packages/python.scm (python-babel, python2-babel): Update to 1.3.

gnu: Move helper code to (gnu system …) modules.

* gnu/packages/grub.scm (<menu-entry>, grub-configuration-file): Move
  to...
* gnu/system/grub.scm: ... here.  New file.
* gnu/packages/linux.scm (<pam-service>, <pam-entry>,
  pam-service->configuration, pam-service->directory,
  %pam-other-services, unix-pam-service): Move to...
* gnu/system/linux.scm: ... here.  New file.
* gnu/system/vm.scm (passwd-file): Move to...
* gnu/system/shadow.scm: ... here.  New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add
  gnu/system/{grub,linux,shadow}.scm.

gnu: Add python-dateutil, python2-dateutil.

* gnu/packages/python.scm (python-dateutil, python2-dateutil): New variables.

guix: python: Create module installation path and add it to PYTHONPATH during
  the installation phase.

* guix/build/python-build-system.scm (get-python-version): New procedure.
* guix/build/python-build-system.scm (install): Create and add path.
* gnu/packages/python.scm (python-setuptools): Drop path creation code.

gnu: linux-initrd: Fix typo.

* gnu/packages/linux-initrd.scm (gnu-system-initrd): Add missing
  argument to 'format' call.

gnu: linux-pam: Add declarative PAM service interface.

* gnu/packages/linux.scm (<pam-service>, <pam-entry>): New record
  types.
  (pam-service->configuration, pam-services->directory,
  unix-pam-service): New procedures.
  (%pam-other-services): New variable.

gnu: Add python-setuptools, python2-setuptools.

* gnu/packages/python.scm (python-setuptools, python2-setuptools):
    New variables.

gnu: isl: Update urls.

* gnu/packages/gcc.scm (isl): Update source and home page url.

guix: python: Add package-with-python2, a procedure rewriting a package
  to compile with Python 2 instead of the default Python 3.

* guix/build-system/python.scm (default-python2, package-with-explicit-python,
    package-with-python2): New procedures.
* guix/build-system/python.scm (python2-pytz, python2-babel): Use
    package-with-python2.