If the script is executed in a CI (like in github actions, with the
install-nix-action) it fails. This changes fixes that use case. In that
scenario, you should provide the --no-commit flag.
Trying to reuse the update scripts used by kakoune/vim to provide the
user with an unified convergence. Some stuff doesn't work yet (parallel
download, caching) but I (anyone else welcome to try too) will improve
it in other PRs.
Move the script to maintainers/scripts/pluginupdate.py.
Importing it from the vim and kakoune update scripts
is done in the commit afterwards to cleanup the diff.