gnu: mkfontdir: Do not propagate 'mkfontscale'.

* gnu/packages/xorg.scm (mkfontdir)[propagated-inputs]: Move
'mkfontscale' to ...
[inputs]: ... here.
[arguments]: Add 'wrap-mkfontdir' phase.

gnu: Add xfd.

* gnu/packages/xorg.scm (xfd): New variable.

gnu: Add xfontsel.

* gnu/packages/xorg.scm (xfontsel): New variable.

gnu: sbcl: Update to 1.3.7.

* gnu/packages/lisp.scm (sbcl): Update to 1.3.7.
[arguments]: During the patch-unix-tool-paths phase, avoid running
substitute* on a utf-16-be encoded file.

Signed-off-by: 宋文武 <iyzsong@gmail.com>

gnu: ecl: Wrap with PATH, CPATH, LIBRARY_PATH, and LD_LIBRARY_PATH.

* gnu/packages/lisp.scm (ecl)[arguments]: Add 'wrap' phase.

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

gnu: ecl: Enable tests.

* gnu/packages/lisp.scm (ecl): Enable tests.

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

gnu: ecl: Update to 16.1.2.

* gnu/packages/lisp.scm (ecl): Update to 16.1.2.

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

gnu: gnupg@2.1: Use 'modify-phases'.

* gnu/packages/gnupg.scm (gnupg@2.1)[arguments]: Use 'modify-phases'
syntax.

gnu: hdup: Update source url.

* gnu/packages/backup.scm (hdup)[source]: Update url.

gnu: gnupg-2.1: Install executable as 'gpg'.

* gnu/packages/gnupg.scm (gnupg-2.1)[arguments]: Add '--enable-gpg2-is-gpg'
to #:configure-flags.

gnu: gnupg@2.0: Add the 'gpg' and 'gpgv' commands.

* gnu/packages/gnupg.scm (gnupg-2.0)[arguments]: Add
'rename-v2-commands' phase.

gnu: gnupg@2.0: Fix typo.

* gnu/packages/gnupg.scm (gnupg@2.0)[arguments]: Fix typo that prevented
gnupg from building.

This is a follow up to 6b547d22952fb30c4419d4f81545353907ab398d.

gnu: exiv2: Update source url.

* gnu/packages/geeqie.scm (exiv2)[source]: Update url.

lint: 'inputs-should-be-native' checks for intltool, itstool and glib:bin.

* guix/scripts/lint.scm (check-inputs-should-be-native): Warn when intltool,
itstool or glib:bin isn't a native-input.
* tests/lint.scm (inputs: glib:bin is probably a native input): Add test.

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

doc: Point out preference of message format.

* doc/contributing.texi (Submitting Patches): Includes a note on
preference of plain text messages with either inline or MIME attachments
and advise contributers to pay attention if their email client breaks the
patches.

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

doc: Explain that contributors can use a pseudonym.

Suggested by ng0 <ng0@we.make.ritual.n0.is>.

* doc/contributing.texi (Contributing): Explain that using a legal name
is not required.

doc: gnupg@2.0: Use 'modify-phases'.

* gnu/packages/gnupg.scm (gnupg-2.0)[arguments]: Use 'modify-phases'.

doc: Explain how to set up Git for signing.

* HACKING (Commit Access): Give instructions on how to set up Git for
signing.

gnu: icecat: Disable parallel build.

* gnu/packages/gnuzilla.scm (icecat)[arguments]: Disable parallel build.

download: Add SourceForge load balancer.

* guix/download.scm (%mirrors)[sourceforge]: Add canonical load balancer for
sourceforge.net.

Signed-off-by: Leo Famulari <leo@famulari.name>