Merge branch 'develop' of https://github.com/LLNL/spack into enhancement/os_detection

.gitignore

.mailmap

bin/spack

etc/spack/repos.yaml

lib/spack/env/cc

lib/spack/env/nag/nagfor

lib/spack/external/argparse.py

lib/spack/external/jsonschema/COPYING

lib/spack/external/jsonschema/README.rst

lib/spack/external/jsonschema/__init__.py

lib/spack/external/jsonschema/__main__.py

lib/spack/external/jsonschema/_format.py

lib/spack/external/jsonschema/_reflect.py

lib/spack/external/jsonschema/_utils.py

lib/spack/external/jsonschema/_validators.py

lib/spack/external/jsonschema/cli.py

lib/spack/external/jsonschema/compat.py

lib/spack/external/jsonschema/exceptions.py

lib/spack/external/jsonschema/schemas/draft3.json

lib/spack/external/jsonschema/schemas/draft4.json