Add methods to model inspector to return SHAP values and associated feature data

[jason-bentley]

Is your feature request related to a problem? Please describe.
After using the model inspector it would be helpful to have an easy way to access the SHAP values and data for use with plotting methods that are part of the base shap library in python.

Describe the solution you'd like
Add methods to the model inspector to allow users to obtain the SHAP values and associated dataset

Describe alternatives you've considered
None.

Additional context
None.