guix: Clean up --help messages.

* guix/scripts/import.scm (show-help): Add newline before a list of
  importers.
* guix/scripts/lint.scm (show-help): Split a long description line.
* guix/scripts/package.scm (show-help): Improve docstrings for --install
  and --remove options.
* guix/scripts/system.scm (show-help): Format actions the same way as
  guix commands and importers are formatted.

gnu: python-numpy: Build against OpenBLAS.

* gnu/packages/python.scm (python-numpy)[inputs]: Use "openblas" instead of
  "atlas".
* gnu/packages/python.scm (python-numpy)[arguments]: Configure build against
  OpenBLAS.

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

Thank Thomas.

doc: Explain where the number of build users comes from.

Suggested by Thomas Schwinge <thomas@codesourcery.com>.

* doc/guix.texi (Build Environment Setup): Explain where the number of build
  users comes from.

guix gc: Add '--verify'.

* guix/scripts/gc.scm (show-help, %options): Add --verify.
  (guix-gc): Handle it.
* doc/guix.texi (Invoking guix gc): Document --verify, and move --optimize
  description right below it.

store: Add 'verify-store' RPC.

* guix/store.scm (operation-id): Add 'verify-store'.
  (verify-store): New procedure.
  (set-build-options): Adjust comment.
* tests/store.scm ("verify-store", "verify-store + check-contents"): New
  tests.

daemon: Always require a signature when importing an archive.

* nix/nix-daemon/nix-daemon.cc (performOp): Pass true as the first argument to
  'performOp'.

guix package: Fix typo in --help message.

* guix/scripts/package.scm (show-help): Align '--show' option properly.

gnu: icecat: Update to 31.7.0-gnu1.

* gnu/packages/patches/icecat-CVE-2015-0797.patch,
  gnu/packages/patches/icecat-CVE-2015-2708-pt1.patch,
  gnu/packages/patches/icecat-CVE-2015-2708-pt2.patch,
  gnu/packages/patches/icecat-CVE-2015-2708-pt3.patch,
  gnu/packages/patches/icecat-CVE-2015-2708-pt4.patch,
  gnu/packages/patches/icecat-CVE-2015-2710-pt1.patch,
  gnu/packages/patches/icecat-CVE-2015-2710-pt2.patch,
  gnu/packages/patches/icecat-CVE-2015-2710-pt3.patch,
  gnu/packages/patches/icecat-CVE-2015-2713-pt1.patch,
  gnu/packages/patches/icecat-CVE-2015-2713-pt2.patch,
  gnu/packages/patches/icecat-CVE-2015-2716.patch: Remove files.
* gnu-system.am (dist_patch_DATA): Remove them.
* gnu/packages/gnuzilla.scm (icecat): Update to 31.7.0-gnu1.  Remove patches.

gnu: tor: Update to 0.2.6.8.

* gnu/packages/tor.scm (tor): Update to 0.2.6.8.
  [native-inputs]: Add python-2.

system: 'hosts-file' is now a file-like object.

Partly fixes <http://bugs.gnu.org/20720>.
Reported by Alex Kost <alezost@gmail.com>.

* gnu/system.scm (default-/etc/hosts): Change 'text-file' to 'plain-file'.
  (maybe-file->monadic): New procedure.
  (operating-system-etc-directory): Use it.
* doc/guix.texi (operating-system Reference, Networking Services): Adjust
  accordingly.

system: 'sudoers' is now a file-like object.

Partly fixes <http://bugs.gnu.org/20720>
Reported by Alex Kost <alezost@gmail.com>.

* gnu/system.scm (etc-directory): Change default #:sudoers value to a
  'plain-file'.  Don't bind it.  Remove #~#$.
  (maybe-string->file): New procedure.
  (operating-system-etc-directory): Use it.
  (%sudoers-specification): Use 'plain-file'.
* doc/guix.texi (operating-system Reference): Adjust accordingly.

doc: Explain "file-like objects".

* doc/guix.texi (G-Expressions): Mention "file-like objects" and explain
  more.

gnu: Add magit-svn.

* gnu/packages/emacs.scm (magit-svn): New variable.

gnu: Add coq.

* gnu/packages/ocaml.scm (coq): New variable.

licenses: Add the Open Publication License 1.0.

* guix/licenses.scm (opl1.0+): New variable.

gnu: Add hevea.

* gnu/packages/ocaml.scm (hevea): New variable.

gnu: Add camlp5.

* gnu/packages/ocaml.scm (camlp5): New variable.

gnu: ocaml: Update to 4.02.1.

* gnu/packages/ocaml.scm (ocaml)[version]: Update to 4.02.1.
  [source]: Use 'version-major+minor'.  Use .xz tarball.
  [home-page]: Update URI.
  [license]: gpl2 -> lgpl2.0.
  [inputs]: Add libx11, gcc:lib, and zlib.  Remove perl.
  [native-inputs]: New field, with perl and pkg-config.
  [arguments]: In #:modules, remove (srfi srfi-1), add (web server).  Use
  'modify-phases'.  Enable parallel build.  Add 'patch-/bin/sh-references' and
  'prepare-socket-test' phases.  Rename 'check-after-install' phase to
  'check'.  Use 'with-directory-excursion' in 'check' phase.  Remove unused
  keyword arguments from custom phases.

gnu: Add devhelp.

* gnu/packages/gnome.scm (devhelp): New variable.