news: Add entry about WSL images.

* etc/news.scm: Add entry.

etc: teams: Define python team scope.

* etc/teams.scm.in (python): Define it.

etc: teams: Define haskell team scope.

* etc/teams.scm.in (haskell): Define it.

doc: Turn example to lisp.

* doc/guix.texi (System Images): Turn example snippets to lisp snippets.

doc: Remove an extra dot.

* doc/guix.texi (System Images): Remove it.

etc: installer: Define installer team scope.

* etc/teams.scm.in (installer): Define it.

etc: teams: Define core team scope.

* etc/teams.scm.in (core): Define it.

etc: teams: Add regular expression support to scopes.

* etc/teams.scm (find-teams-by-scope): Differentiate between raw strings
and regexps.  Make raw string matches strict.

Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>

etc: teams: Add scope support.

Add a scope list to each team.  This list defines all the files and
directories that are mentored by the team.

Also add a cc-members command that takes two Git revision strings as input,
add returns the members that should be CC'ed given the files impacted between
the two revisions.

* etc/teams.scm.in (<team>)[scope]: New field.
(team, list-teams): Adapt those procedures.
(find-team-by-scope, diff-revisions): New procedures.
(main): Add a "cc-members" command.
* doc/contributing.texi ("Teams"): Document it.
("Sending a Patch Series"): Adapt it.

system: images: Add a TODO comment.

* gnu/system/image.scm (system-tarball-image): Add it.

gnu: emacs-piem: Do not propagate B4.

* gnu/packages/emacs-xyz.scm (emacs-piem)[arguments]: Add CONFIGURE phase to
avoid propagating B4.
[inputs]: Add B4.
[propagated-inputs]: Remove B4.

gnu: emacs-piem: Fix license.

* gnu/packages/emacs-xyz.scm (emacs-piem)[license]: Set to GPL3+.

gnu: emacs-slack: Update to ff46d88.

* gnu/packages/emacs-xyz.scm (emacs-slack): Update to ff46d88.

Signed-off-by: Nicolas Goaziou <mail@nicolasgoaziou.fr>

gnu: Add emacs-piem.

* gnu/packages/emacs-xyz.scm (emacs-piem): New variable.

Signed-off-by: Nicolas Goaziou <mail@nicolasgoaziou.fr>

gnu: emacs-perspective: Update to 2.18.

* gnu/packages/emacs-xyz.scm (emacs-perspective): Update to 2.18.

gnu: emacs-ement: Update to 0.2.

* gnu/packages/emacs-xyz.scm (emacs-ement): Update to 0.2.

gnu: emacs-mentor: Update to 0.4.

* gnu/packages/emacs-xyz.scm (emacs-mentor): Update to 0.4.

gnu: emacs-subed: Update to 1.0.10.

* gnu/packages/emacs-xyz.scm (emacs-subed): Update to 1.0.10.

gnu: Add python-icdiff.

* gnu/packages/python-xyz.scm (python-icdiff): New variable.

Signed-off-by: Julien Lepiller <julien@lepiller.eu>

gnu: Add python-editables.

* gnu/packages/python-build.scm (python-editables): New variable.

Signed-off-by: Julien Lepiller <julien@lepiller.eu>