feat: add Naive Bayes and CategoricalNB (#15)

* feat: Implement Naive Bayes classifier

* Implement CategoricalNB

src/lib.rs

@@ -85,6 +85,8 @@ pub mod math;
 /// Functions for assessing prediction error.
 pub mod metrics;
 pub mod model_selection;
+///  Supervised learning algorithms based on applying the Bayes theorem with the independence assumptions between predictors
+pub mod naive_bayes;
 /// Supervised neighbors-based learning methods
 pub mod neighbors;
 pub(crate) mod optimization;