Correct LLNL LGPL license template for clarity.

LICENSE

bin/sbang

bin/spack

bin/spack-python

lib/spack/env/cc

lib/spack/external/nose/LICENSE

lib/spack/llnl/__init__.py

lib/spack/llnl/util/__init__.py

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/__init__.py

lib/spack/spack/abi.py

lib/spack/spack/architecture.py

lib/spack/spack/build_environment.py