gexp: Remove leftover parameter.

* guix/gexp.scm (gexp->sexp): Remove #:outputs parameter.  Adjust
  callers accordingly.
Update 'TODO'.
gnu-maintenance: Avoid network access in 'gnu-package?'.

* guix/gnu-maintenance.scm (gnu-package?): Add 'mirror-type' procedure.
  Resort to 'official-gnu-packages' only when 'mirror-type' returns #f.
gnu: guile-ncurses: Build with Unicode support.

* gnu/packages/guile.scm (guile-ncurses)[arguments]: Pass
  "--with-ncursesw".
derivations: Micro-optimize 'derivation'.

* guix/derivations.scm (derivation->string): New procedure.
  (derivation-hash, derivation): Use it.
  Memoization here yields a 5% improvement on "guix build -e '(@ (gnu
  packages emacs) emacs)' -n --no-substitutes".
gnu: Add gmsh

* gnu/packages/maths.scm (gmsh): New variable
gnu: gmsh: Fix typos

* gnu/packages/maths.scm (gmsh): Fix typo and space aftern
  end-of-sentence.
gnu: calcurse: Fix module definition.

* gnu/packages/calcurse.scm: Define calcurse module correctly.
system: Add (guix build activation).

* gnu/services/dmd.scm (dmd-configuration-file): Remove 'etc'
  parameter.  Move /etc activation code to...
* guix/build/activation.scm: ... here; new file.
* gnu/system.scm (operating-system-boot-script): Augment script: add
  (guix build activation) to the load path; call 'activate-etc'.
* Makefile.am (MODULES): Add guix/build/activation.scm.
linux-initrd: Allow setuid binaries from the unionfs to run.

* guix/build/linux-initrd.scm (boot-system): Pass the 'suid' option to
  UNIONFS.
system: Add support for setuid binaries.

* gnu/system.scm (<operating-system>)[pam-services, setuid-programs]:
  New fields.
  (etc-directory)[bashrc]: Prepend /run/setuid-programs to $PATH.
  (operating-system-etc-directory): Honor
  'operating-system-pam-services'.
  (%setuid-programs): New variable.
  (operating-system-boot-script): Add (guix build utils) to the set of
  imported modules.  Call 'activate-setuid-programs' in boot script.
* gnu/system/linux.scm (base-pam-services): New procedure.
* guix/build/activation.scm (%setuid-directory): New variable.
  (activate-setuid-programs): New procedure.
* build-aux/hydra/demo-os.scm: Add 'pam-services' field.
gnu: Add sudo.

* gnu/packages/admin.scm (sudo): New variable.
gexp: Add pretty printer.

* guix/gexp.scm (write-gexp): New procedure.
  <top level>: Add call to 'set-record-type-printer!'.
gnu: Propagate necessary inputs for sdl-image.

* gnu/packages/sdl.scm (sdl-image): Propagate jpeg, png, and tiff
  libraries.
gnu: Add abbaye.

* gnu/packages/games.scm (abbaye): New variable.
gnu: Add petsc

* gnu/packages/maths.scm (petsc): New variable.
  (petsc-complex): New variable.
* gnu/packages/patches/petsc-fix-threadcomm.patch: New patch.
* gnu-system.am (dist_patch_DATA): Add it.
system: Add 'sudo' to the setuid programs, and handle /etc/sudoers.

* gnu/system.scm (<operating-system>)[groups]: Change default to just
  the 'root' group.
  [sudoers]: New field.
  (etc-directory): Add #:sudoers parameter.  Add 'sudoers' to the
  file union.
  (operating-system-etc-directory): Pass #:sudoers to 'etc-directory'.
  (%setuid-programs): Add 'sudo'.
  (%sudoers-specification): New variable.
* gnu/system/linux.scm (base-pam-services): Add 'sudo'.
* build-aux/hydra/demo-os.scm: Add 'groups' field; add 'guest' to the
  'wheel' group.
gexp: Add support for 'origin?' objects in 'ungexp' forms.

* guix/gexp.scm (lower-inputs, gexp-inputs, gexp->sexp,
  canonicalize-reference): Add 'origin?' case.
* guix/monads.scm (origin->derivation): New procedure.
* tests/gexp.scm ("one input origin"): New test.
monads, gexp: Remove unintended dependency on (gnu packages …).

* guix/gexp.scm (gexp->derivation, gexp->script): Use 'default-guile'
  instead of an explicit reference to 'guile-final'.
  (default-guile): New procedure.
* guix/monads.scm (run-with-store)[default-guile]: New procedure.
  Use it.
download: Rewrite using gexps.

* guix/download.scm (gnutls-derivation): Remove.
  (gnutls-package): New procedure.
  (url-fetch): Rewrite using 'gexp->derivation'.