PR #15212 added a new connect_timeout option that can be overridden
using fetch_options but had to specified per-version. This adds a new
per-package variable that can be used to override fetch_options for
all versions in the package. This includes connect_timeout as well
as 'cookie' (e.g. for the jdk package).
Packages can combine package-level fetch_options with per-version
fetch_options, in which case the version fetch_options completely
override the package-level fetch_options.
This commit includes tests for the added behavior.
We'd like to use a consistent checksum scheme everywhere so that we can:
a) incorporate archive checksums into our specs and have a
consistent hashing algorithm across all specs.
b) index mirrors with a consistent type of checksum, and not one that
is dependent on how spack packages are written.
- [x] convert existing md5, sha224, sha512, sha1 checksums to sha256
- 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
