Move to h5netcdf

[f-brinkmann]

Moving to https://github.com/h5netcdf/h5netcdf would remove a binary dependency. It could be checked if this is worth the effort.

[mberz]

While it's not going to remove binary dependencies altogether, it may be a good step to take.
As far as I remember, the h5netcdf package also comes with a bit of a performance improvement compared to the original netcdf implementation. My experience with it is however a couple of years in the past already, so no guarantees that it's still accurate.
Additionally, I remember that netcdf was not always the best in terms of dependency management/resolution. At least when installing via conda I remember a couple of hick-ups every now and then.

[mberz]

We discussed that this might also a potential workaround for #140
@hoyer-a will explore this option

[hoyer-a]

So, the legacy api from h5netcdf (import h5netcdf.legacyapi as netCDF4) is no drop in replacement and it might take a little more effort to move to h5netcdf because of some differences.

The numpy deprecation warning from #140 should be fixed soon (see #140 (comment)), so we might reconsider if or when we should move away from netCDF4.

[mberz]

Thanks for researching this. Let's keep it at low priority then.