- remove the old LGPL license headers from all files in Spack
- add SPDX headers to all files
- core and most packages are (Apache-2.0 OR MIT)
- a very small number of remaining packages are LGPL-2.1-only
* Use GitLab's API endpoint for fetching a git snapshot.
* More GitLab packages use the API.
* find_list_url for GitLab's API URLs.
* Flake8
* Url for 'hacckernels'.
* Check GitLab API regexps before the non-API ones.
