environment: Fix setting writable? on networking related files

* guix/scripts/environment.scm (launch-environment/container): Include the
  file name in the call to string=? when deciding if the file should be
  writable.

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

gnu: Add font-awesome.

* gnu/packages/fonts.scm (font-awesome): New variable.

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

gnu: Add opencascade-oce.

* gnu/packages/maths.scm (opencascade-oce): New variable.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

store: Add 'add-data-to-store'.

* guix/serialization.scm (write-bytevector): New procedure.
(write-string): Rewrite in terms of 'write-bytevector'.
* guix/store.scm (write-arg): Add 'bytevector' case.
(add-data-to-store): New procedure, from former 'add-text-to-store'.
(add-text-to-store): Rewrite in terms of 'add-data-to-store'.
* tests/store.scm ("add-data-to-store"): New test.

gnu: Add catimg.

* gnu/packages/image-viewers.scm (catimg): New variable.

Signed-off-by: Kei Kebreau <kei@openmailbox.org>

gnu: Add dub.

* gnu/packages/ldc.scm (dub): New variable.

gnu: khal: Update to 0.9.1.

* gnu/packages/calendar.scm (khal): Update to 0.9.1.

doc: Fix typo.

* doc/guix.texi (ocaml-build-system): Replace ocaml with OCaml.

doc: Document ocaml-build-system.

* doc/guix.texi (Build Systems) [ocaml-build-system]: New definition.

gnu: emacs-org: Update to 20170124.

* gnu/packages/emacs.scm (emacs-org): Update to 20170124.

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

gnu: wireshark: Update to 2.2.4.

* gnu/packages/networking.scm (wireshark): Update to 2.2.4.

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

gnu: asymptote: Update to 2.39

* gnu/packages/plotutils.scm (asymptote): Update to 2.39.

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

gnu: vim: Update to 8.0.0257.

* gnu/packages/vim.scm (vim): Update to 8.0.0257.

gnu: Add GNU Freetalk.

* gnu/packages/messaging.scm (freetalk): New variable.

Signed-off-by: Mathieu Lirzin <mthl@gnu.org>

gnu: exfat-utils: Update to 1.2.6.

* gnu/packages/mtools.scm (exfat-utils): Update to 1.2.6.

gnu: fuse-exfat: Update to 1.2.6.

* gnu/packages/linux.scm (fuse-exfat): Update to 1.2.6.

build-system/python: 'package-with-explicit-python' uses 'eq?' memoization.

* guix/build-system/python.scm (package-with-explicit-python): Use
'mlambdaq' instead of 'mlambda'.  This does not change the <package>
graph and has no visible impact on performance.

gnu-maintenance: 'gnu-package?' uses 'eq?' memoization.

* guix/gnu-maintenance.scm (gnu-package?): Use 'mlambdaq' instead of
'mlambda'.

packages: Remove 'define-memoized/v' and use 'mlambdaq' instead.

* guix/packages.scm (define-memoized/v): Remove.
(package-transitive-supported-systems): Use 'mlambdaq' instead of
'define-memoized/v'.
(package-input-rewriting)[replace]: Likewise.

Use 'mlambda' instead of 'memoize'.

* gnu/packages.scm (find-newest-available-packages): Use 'mlambda'
instead of (memoize (lambda ...) ...).
* gnu/packages/bootstrap.scm (package-with-bootstrap-guile): Likewise.
* guix/build-system/gnu.scm (package-with-explicit-inputs)[rewritten-input]:
Likewise.
* guix/build-system/python.scm (package-with-explicit-python)[transform]:
Likewise.
* guix/derivations.scm (derivation->string): Likewise.
* guix/gnu-maintenance.scm (gnu-package?): Likewise.
* guix/modules.scm (module-file-dependencies): Likewise.
* guix/scripts/graph.scm (standard-package-set): Likewise.
* guix/scripts/lint.scm (official-gnu-packages*): Likewise.
* guix/store.scm (store-regexp*): Likewise.
* guix/utils.scm (location): Likewise.