Make Spack core PEP8 compliant.

.flake8

bin/spack

lib/spack/llnl/util/filesystem.py

lib/spack/llnl/util/lang.py

lib/spack/llnl/util/link_tree.py

lib/spack/llnl/util/lock.py

lib/spack/llnl/util/tty/__init__.py

lib/spack/llnl/util/tty/colify.py

lib/spack/llnl/util/tty/color.py

lib/spack/llnl/util/tty/log.py

lib/spack/spack/abi.py

lib/spack/spack/architecture.py

lib/spack/spack/cmd/__init__.py

lib/spack/spack/cmd/activate.py

lib/spack/spack/cmd/arch.py

lib/spack/spack/cmd/cd.py

lib/spack/spack/cmd/clean.py

lib/spack/spack/cmd/common/arguments.py

lib/spack/spack/cmd/compiler.py

lib/spack/spack/cmd/compilers.py