Added
- added `cross_validate()` methods to `Forecaster` and `MVForecaster` objects, which can now be used for the same purposes as `tune()` but with cross validation
- added `cross_validate` as a (bool) argument to the `Forecaster.tune_test_forecast()`, `Forecaster.reduce_Xvars()`, `MVForecaster.tune_test_forecast()`, and `notebook.tune_test_forecast()` functions
- added "CrossValidated" key to history dict in `Forecaster` and `MVForecaster` objects
Changed
- if np.nan is passed as a normalizer value, it will convert to None so that it can be used
Fixed