[PAPER 1] add gumbel type for mle fit. add study_visualizer_for_shape_repartition both for gumbel VS stationary and stationary VS non-stationary

[EUROCODE][DRAWING PER REGION] modify test region eurocode. add test_ gev temporal bayesian. add stationary version for the Bayesian. refactor utils at the root, to root_uils to avoid weird import issues.

[EXTREME ESTIMATOR] refactor margin_fits folder. extreme estimator folder. and extreme_models folder