Custom test viz

[justmytwospence]

It would be neat if you could substitute any visualization for the stacked bar chart that is currently there. I've seen Shiny apps in the past that have code editor windows that allow you to type/execute arbitrary code. This feature would really level up the usefulness here: you could paste in the code for a plot that you are making (on second thought, uploading a serialized plot object itself might be better), and then tweak the way that particular plot looks to your heart's content.

I might hack on this at some point in the future, but thought I would leave the idea here as well.

[bchartoff]

I'm with you on this one, by the way (sorry for the delayed response!), thinking about adding this feature soon, when life calms down.