Clean up Categorical Visualization Options

[alexsb]

For Items:

• Matrix (see New Default Small-C Categorical View #488)
• Color
• Text/Label (see Default Vis for categorical column with large N: Text #490, or "no visualization", see Separate Label from Visualizations #491)
• Symbols (not sure we need it?)

This means removing UpSet and Table visualization.

For Groups:

• Histogram
• Distribution Bar
• Matrix -> this should be grayscale and the color should be scaled by the number of items in the group

For Summary: same as groups.
PLUS: a search option, see #490