added tutorial notebook for example dataset

Created by: rettigl

I added a notebook with test data on zenodo, please have a look. It requires the mpes package to generate the dataframe, and at the moment the version that is packaged cannot be installed together with sed (it pins h5py). I made a fork that does not do this at https://github.com/rettigl/mpes Not sure if we should reflect this in the dependencies. I intend to include this into the main mpes package, and maybe also make a new pypi package, but I don't really know how to do that. I also did not thest with the new binning branch