paramters for interactiveheatmap

[curtislisle]

Row index selection - We don't always know which column would be the column to use for row labels, and we can't depend on the first column always, even though we've tried requesting this. I suggest we allow a column header to be selected as a parameter from the Visualization tab with the default as the first column.

Cell size - It would provide flexibility if the current cell size was made a default, but the user was allowed to adjust it (e.g. make it larger) to offer more control over the final table rendering.

[jeffbaumes]

Those seem like reasonable parameters.