ECMWF licence

[floriankrb]

ECMWF packages using the Apache 2 licence usually have this licence https://github.com/ecmwf/climetlab/blob/develop/LICENSE

Along with a header in any possible files (excluding files not supporting it such as yaml, json, binary, etc.):

# (C) Copyright 2020 ECMWF.
#
# This software is licensed under the terms of the Apache Licence Version 2.0
# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
**# In applying this licence, ECMWF does not waive the privileges and immunities
# granted to it by virtue of its status as an intergovernmental organisation
# nor does it submit to any jurisdiction.**
#

And in the README too.

I believe this package should be updated with the correct licence, and the generated conda packages should also include the same licence with the same writing.

FYI, ECMWF guidelines are here: https://confluence.ecmwf.int/display/DS/Checklist+for+new+packages+on+Github but I am not sure if this page is public.