Refactoring/notebook cleanup

Setup a common library for methods used throughout the different notebooks used so far. This library has to be the entry point for any forthcoming notebooks/proto in order that they are all symchronized. In order to setup the parameters, please refer to d19-thom.yml as an example. Ideally, we should end up with a single workflow script and a collection of yml files for each prototypes. The workflow has to be the same, inly its parameters change. I also took that opportunity to implement many new filters. Fell free to add any modifications to this if you feel the need to.