Restructure folders

Since we wanted to keep/restore the original scripts in Scripts/, I suggest in the process of that to restructure the folders such that pyALF will take the form of a proper Python package and all the functionality will be accessible through import py_alf. I suggest the following structure:

    pyALF/
    └── py_alf/
        └── __init__.py
        └── cli/
             └── What is currently in /Scripts
        ├── alf_source.py
        ├── simulation.py
        ├── lattice.py
        └── ...
    ├── doc/
    ├── Notebooks/
    └── Scripts/

Does someone know someone who is experienced with building python packages and can give their input on the layout?