document how to do hyperparameter search for C and gamma

[NickleDave]

as @URSUroman suggested in #68

I was however wondering if a user wants to use the svm algorithm for the classification, is there a documentation on how to choose the hyperparameters C and gamma in the Select.yml file? The default parameters worked for me but i wonder if it will always be the case for the users.

should at least point to
https://scikit-learn.org/stable/auto_examples/model_selection/plot_grid_search_digits.html
which is basically what I have usually done