Scalecast

Added
- if there are not enough observations to use in cross validation (usually because too many AR terms were added), an error is raised when calling the `Forecater.cross_validate()` and `MVForecaster.cross_validation()` functions
Changed
- no `Forecaster.auto_Xvar_select()` no longer raises errors if more AR terms passed to max_ar argument than the model is able to estimate
Fixed
- `Forecaster.determine_best_series_length()` will no longer fail if the min_obs arg value is greater than the amount of observations in the series
- found more instances where `TypeError`s should not be raised (such as passing an `int64` type when `int` is required)
- fixed an issue that occurs after selecting Xvars with `Forecaster.auto_Xvar_select()` on an integrated series then loading to `MVForecaster`
- fixed the error raised when 0 or less is passed to the `Forecaster.set_validation_length()` and `MVForecaster.set_validation_length()` functions

Added
- added the `Forecaster.auto_Xvar_select()` method
- added a check for NAs in `Forecaster` and `MVForecaster` when evaluating grids and validation metric is mape. a descriptive error is raised if NAs are found (10)
- added `Forecaster.drop_all_Xvars()`
- added `Forecaster.determine_best_series_length()`
- added `Forecaster.restore_series_length()`
Changed
- removed deprecated functions identified and labeled in 0.13.1
- `Forecaster.keep_smaller_history()` can now accept numpy int types as an argument.
Fixed

Added
- added grids_file attribute to `Forecaster` and `MVForecaster` objects, as well as `set_grids_file()` method to both objects.
Changed
Fixed

Added
- added probabilistic argument option to `auxmodels.mlp_stack()` function.
- added Xvars argument to `auxmodels.auto_arima()` function.
Changed
- made it so that an error is raised earlier when using `Forecaster.ingest_Xvars_df()` incorrectly.
Fixed
- fixed an issue with `auxmodels.mlp_stack()` where `**kwargs` were not being passed correctly.

Added
- added error arg to `Forecaster.tune_test_forecast()` and `MVForecater.tune_test_forecast()` methods.
Changed
- took out an error check that was redundant and not even working
Fixed
- fixed some documentation syntax for new objects added last dist

Added
- added `auxmodels` module with `auto_arima()` and `mlp_stack()` functions
- added pmdarima as an optional requirement to make auto_arima work
- added `util.metrics` class
- added `Forecaster.reeval_cis()` and `MVForecaster.reeval_cis()` methods
Changed
Fixed