- [x] add `concretize.lp`, `spack.yaml`, etc. to licensed files
- [x] update all licensed files to say 2013-2021 using
`spack license update-copyright-year`
- [x] appease mypy with some additions to package.py that needed
for oneapi.py
* diffutils: Changed the handling of undeclared functions from warning to error.
* diffutils: Change the handling of warnings or error
* Delete '-Werror=implicit-function-declaration'
* Add '-Qunused-arguments'
Users can now list mirrors of the main url in packages.
- [x] Instead of just a single `url` attribute, users can provide a list (`urls`) in the package, and these will be tried by in order by the fetch strategy.
- [x] To handle one of the most common mirror cases, define a `GNUMirrorPackage` mixin to handle all the standard GNU mirrors. GNU packages can set `gnu_mirror_path` to define the path within a mirror, and the mixin handles setting up all the requisite GNU mirror URLs.
- [x] update all GNU packages in `builtin` to use the `GNUMirrorPackage` mixin.
- 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
* bison: Add missing build dependencies
bison also depends on cmp, which is currently not available in Spack.
* help2man: Add missing build dependency
* m4: Fix build with newer versions of glibc
* openssl: Add missing build dependency
openssl's configure script is actually a Perl script.
* texinfo: Add missing perl dependency
* diffutils: New package
* findutils: Fix build with newer versions of glibc
* mvapich2, mpich: Add missing findutils dependency
