text: Title: Addition: A SimplifiedClassifierDashboard
  Body: The default dashboard can be very overwhelming with lots of tabs, toggles and dropdowns. It would be nice to offer a simplified version. This can be built as a custom `ExplainerComponent` and included in custom, so that you could e.g.:
  
  ```python
  from explainerdashboard import ClassifierExplainer, ExplainerDashboard
  from explainerdashboard.custom import SimplifiedClassifierDashboard
  
  explainer = ClassifierExplainer(model, X, y)
  ExplainerDashboard(explainer, SimplifiedClassifierDashboard).run()
  ```
  
  It should probably include at least:
  - Confusion matrix + one other model quality indicator
  - Shap importances
  - Shap dependence
  - Shap contributions graph
  
  And ideally would add in some `dash_bootstrap_components` sugar to make it look extra nice, plus perhaps some extra information on how to interpret the various graphs. 