ScatterWidget return labels instead of colors

[Dristro]

Noticed that the .data_as_pandas returns a df containing both colors and labels. Whereas the .data_as_X_y returns colors, which isn't very useful when interpreting and working with the data.

Update: Modified the ScatterWidget class so that .data_as_X_y now returns labels instead of colors. Question: Was there a specific reason for returning color instead of label? Happy to discuss if there's a particular use case for it!