* xeus: new package
cppzmq: add version 4.3.0
zeromq: make libsodium optional, on by default
* xeus: add patch so it builds, add new version
nlohmann-json: add more versions
cryptopp: add more versions
* xeus: flake8
* xeus: fix license
- 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
Adds the cppzmq library, adding a C++ API to ZeroMQ (libzmq). In order to find the autotools-build libzmq, this requires the upcoming cppzmq release (or development branch).
