system: Skeleton '.bashrc' now exports the 'SHELL' variable.

* gnu/system/shadow.scm (default-skeletons)[bashrc]: Export 'SHELL'.

system: Adjust '.bashrc' skeleton for non-interactive SSH sessions.

* gnu/system/shadow.scm (default-skeletons)[bashrc]: Source /etc/profile
  when in a non-interactive SSH session.

system: Don't compare <pam-service> objects with 'equal?'.

Fixes <http://bugs.gnu.org/20037>.
Reported by 宋文武 <iyzsong@gmail.com> and Tomáš Čech.

* gnu/system.scm (operating-system-etc-directory): Remove call to
  'delete-duplicates'.
* gnu/system/linux.scm (pam-services->directory)[builder]: Add call to
  'delete-duplicates'.

doc: Add 'packages' field to OS configuration template.

* gnu/system/os-config.tmpl (packages): New field.

Merge branch 'master' into core-updates

artwork: Update snapshot to GuixSD branding.

* gnu/artwork.scm (%artwork-repository): Update to new "GuixSD"
  branding.
* gnu/system/grub.scm (%background-image, %default-theme): Adjust
  accordingly.

linux-initrd: Add 'isci' module, needed for some SAS controllers.

Encountered on a Dell Precision T3600.

* gnu/system/linux-initrd.scm (base-initrd)[linux-modules]: Add isci.

gnu: wpa-supplicant: Add dbus support; add wpa-supplicant-light.

* gnu/packages/admin.scm (wpa-supplicant-light): New variable containing the
  previous dbus-free package, but renamed.  Remove outdated TODO comments.
  (wpa-supplicant): Now inherits from wpa-supplicant-light but adds dbus
  support.
* gnu/system/install.scm (installation-os): Use wpa-supplicant-light.

system: Add bindings to configure libc's NSS.

* gnu/system/nss.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.
* gnu.scm (%public-modules): Add it.
* gnu/system.scm (<operating-system>)[name-service-switch]: New field.
  (etc-directory): Add #:nss parameter and honor it.
  (operating-system-etc-directory): Adjust call accordingly.
* doc/guix.texi (operating-system Reference): Document
  'name-service-switch'.
  (Name Service Switch): New section.

install: Add iw to the packages.

* gnu/system/install.scm (installation-os)[packages]: Add IW.

linux-initrd: Add USB kernel modules to the default initrd.

* gnu/system/linux-initrd.scm (base-initrd)[linux-modules]: Add
  usb-storage, uas, usbkbd, and usbhid.
* gnu/system/vm.scm (system-disk-image): Remove #:extra-modules argument
  to 'base-initrd'.

install: Mention GSD.

* gnu/system/install.scm (installation-services): Mention the Guix
  System Distribution.

doc: Add services to the configuration template.

* gnu/system/os-config.tmpl (services): New field.

install: Make sure 'info' can decompress the Info files.

* gnu/system/install.scm (log-to-info): Add GZIP to $PATH.

system: Add "en_US.UTF-8" to the default locales, for backward compatibility.

* gnu/system/locale.scm (%default-locale-definitions): Add
  "en_US.UTF-8".

monads: Move '%store-monad' and related procedures where they belong.

This turns (guix monads) into a generic module for monads, and moves the
store monad and related monadic procedures in their corresponding
module.

* guix/monads.scm (store-return, store-bind, %store-monad, store-lift,
  text-file, interned-file, package-file, package->derivation,
  package->cross-derivation, origin->derivation, imported-modules,
  compiled, modules, built-derivations, run-with-store): Move to...
* guix/store.scm (store-return, store-bind, %store-monad, store-lift,
  text-file, interned-file): ... here.
  (%guile-for-build): New variable.
  (run-with-store): Moved from monads.scm.  Remove default value for
  #:guile-for-build.
* guix/packages.scm (default-guile): Export.
  (set-guile-for-build): New procedure.
  (package-file, package->derivation, package->cross-derivation,
  origin->derivation): Moved from monads.scm.
* guix/derivations.scm (%guile-for-build): Remove.
  (imported-modules): Rename to...
  (%imported-modules): ... this.
  (compiled-modules): Rename to...
  (%compiled-modules): ... this.
  (built-derivations, imported-modules, compiled-modules): New
  procedures.
* gnu/services/avahi.scm, gnu/services/base.scm, gnu/services/dbus.scm,
  gnu/services/dmd.scm, gnu/services/networking.scm,
  gnu/services/ssh.scm, gnu/services/xorg.scm, gnu/system/install.scm,
  gnu/system/linux-initrd.scm, gnu/system/shadow.scm, guix/download.scm,
  guix/gexp.scm, guix/git-download.scm, guix/profiles.scm,
  guix/svn-download.scm, tests/monads.scm: Adjust imports accordingly.
* guix/monad-repl.scm (default-guile-derivation): New procedure.
  (store-monad-language, run-in-store): Use it.
* build-aux/hydra/gnu-system.scm (qemu-jobs): Add explicit
  'set-guile-for-build' call.
* guix/scripts/archive.scm (derivation-from-expression): Likewise.
* guix/scripts/build.scm (options/resolve-packages): Likewise.
* guix/scripts/environment.scm (guix-environment): Likewise.
* guix/scripts/system.scm (guix-system): Likewise.
* doc/guix.texi (The Store Monad): Adjust module names accordingly.

Merge branch 'master' into core-updates

install: Use a low-memory nscd caching policy.

* gnu/system/install.scm (%nscd-minimal-caches): New variable.
  (installation-services): Use as 'nscd-service' argument.

Merge branch 'master' into 'core-updates'.

system: grub: Make sure the font and background image are always found.

* gnu/system/grub.scm (eye-candy): Add 'search --file --set'.