setup.py file change needed

[EmmerichTech]

To whom it may concern,

When downloading the latest version of this repository I found on setup, the following change is needed to be made to the setup file:
From package_data={'nemweb': 'tests/2018_09_21.pkl'}
To package_data={'nemweb': ['tests/2018_09_21.pkl']}

As the package_data dictionary most be a list of strings.
Cheers, some users may get caught.