Martha King

- similar component to the label picker - on change recall process_to_json_text - update process_to_json_text to take an optional param of selected column for x - update the get_x_value_type to...

- should only require changes in Visualization.enso file, add indication that SSRM is being used or not then update get_rows_for_table to also take Vectors.

> Not necessarily for this PR but a general discussion - while Nulls indicator is something that probably makes sense to display always, should we maybe display the Leading/Trailing whitespace...