Merge remote-tracking branch 'upstream/develop' into env-draco

lib/spack/docs/basic_usage.rst

lib/spack/spack/build_environment.py

lib/spack/spack/cmd/uninstall.py

lib/spack/spack/modules.py

lib/spack/spack/test/__init__.py

lib/spack/spack/test/cmd/__init__.py

lib/spack/spack/test/cmd/uninstall.py

lib/spack/spack/test/database.py

lib/spack/spack/test/install.py

lib/spack/spack/test/mock_database.py

...spack/repos/builtin.mock/packages/cmake-client/package.py

var/spack/repos/builtin.mock/packages/cmake/package.py

var/spack/repos/builtin/packages/dbus/package.py

var/spack/repos/builtin/packages/dealii/package.py

...ack/repos/builtin/packages/environment-modules/package.py

var/spack/repos/builtin/packages/git/package.py

var/spack/repos/builtin/packages/libxcb/package.py

var/spack/repos/builtin/packages/metis/package.py

var/spack/repos/builtin/packages/modules/package.py

var/spack/repos/builtin/packages/netcdf-cxx/package.py