[bug#32059] Improve etc/snippets

[Arun Isaac <arunisaac@systemreboot.net>]

Patch 1 adds the android-ndk and scons build systems as possibilities for the
build-system field in the package snippet.

Patch 2 modifies the package snippet so that 'origin' comes on the next line
after 'source'. I feel this is better because it makes better use of space
(less whitespace on the left of the source description). Often, this is
necessary to not run afoul of the line length limitations of `guix lint`.

Patch 3 adds a guix commit message snippet for changing the home page of
packages to HTTPS.

Patch 1 is uncontroversial. But, I don't know if others would agree on patches
2 and 3. Anyways, I am just submitting them here for consideration.

Arun Isaac (3):
  etc: snippets: Add new build systems to package snippet.
  etc: snippets: Improve indentation in the package snippet.
  etc: snippets: Add guix-commit-message-use-https-home-page.

 doc/contributing.texi                                          | 3 ++-
 etc/snippets/scheme-mode/guix-package                          | 7 +++++--
 etc/snippets/text-mode/guix-commit-message-use-https-home-page | 9 +++++++++
 3 files changed, 16 insertions(+), 3 deletions(-)
 create mode 100644 etc/snippets/text-mode/guix-commit-message-use-https-home-page

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2.15.1