Make MDTF-diagnostics pip installable

[wrongkindofdoctor]

What problem will this feature solve?
Configuring the repo to be pip-installable will allow it to fit more easily into workflows, and provide and option for users who prefer manage MDTF via pip in their own virtual environments
Describe the solution you'd like
Reconfigure the repo to adhere to PIP package structure, add required configuration files, and upload the project to PyPI
Describe alternatives you've considered
Install repo with pip using the existing html path, adding log to setup to the existing virtual environment and manually add paths to directories not automatically included by pip. This approach is fast and may work with the current GFDL workflow configuration, but is not robust or easily maintainable.
Additional context