This release is mainly about documentation. * pyAgrum * Fixing last references to LIP6's notebooks instead of rtd's notebooks (thanks to Benjamin Datko). * Adding 'Book of Why's notebooks to readthedoc's documentation. * Updating Notebooks and thumbnails. * Improving documentation coverage for pyAgrum class methods (from 86.19% to 87.05%) * `gum.BNLearner.learnEssentialGraph` for all learning algorithm. * Better wrapping of `pyAgrum.BNLearner.setPossibleEdges()`.