Licence does not follow ECMWF guidelines

[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 you have access to this page.

[alexamici]

@floriankrb we are waiting on C3S to make a decision on the details of the license, the default copyright holder, the boilerplate text and where to add the license for packages for the CopDS project.

Those may differ from the ones for core ECMWF packages. We aim to support both styles.