Numba-mpi

- default tag is set to 0 for `send()`

- added support for `ANY_TAG` and `ANY_SOURCE` in recv().

URLs updated in setup.py file (atmos-cloud-sim-uj -> numba-mpi)

Repository moved from atmos-cloud-sim-uj to numba-mpi, README links updated accordingly.

- fix `njit` support in `barier` and `bcast` (and improve related test coverage)
- test code cleanups (lists -> tuples wherever possible for clarity)

thanks Delcior!

- added `.zenodo.json` files with metadata for Zenodo release archival