* py-jupyter-console: Add version 5.2.0
* py-jupyter-core: add version 4.4.0
* py-lxml: add version 4.2.5
* py-zmq: add version 17.1.2
* py-terminado: add version 0.8.1
* py-pexpect: add version 4.6.0
* py-pytables: add version 3.4.4
- 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
