Hyperparam tuning

It would be nice to have support for [hyperparam search](https://scikit-learn.org/stable/modules/generated/sklearn.model_selection.GridSearchCV.html#sklearn.model_selection.GridSearchCV) functionality. In addition to [KFold](https://docs.rs/smartcore/latest/smartcore/model_selection/index.html) cross validation. I'm planning to start work on a draft unless this is already underway.