Molecular atmosphere refactoring 2
This merge request addresses the following issues:
- The examples (notebooks) are running
- Docstrings were added
- Files were formatted with black in order to satisfy PEP8 coding style
- Some first unit tests were added
- Some minor changes in functionality
Functionality wise, the calibration products are not final yet. We need to clarify couple of questions with the experts. The implementation after that will be straightforward. Such questions are marked with inline comments starting with FIXME.
In order to run the molecular atmosphere calibration, one needs to install the molecularprofiles package (branch test/grib2_test) Shall we install the package together with calibpipe? That would be the object of a future pull request.