[UI] Add ability to render query plans

[andygrove]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
I can currently download query plans in dot format from the scheduler REST API and then use graphviz to transform them into images. I would like to be able to view them directly in the UI as well.

Describe the solution you'd like
Perhaps https://github.com/magjac/d3-graphviz will help

Describe alternatives you've considered
None

Additional context
None

[onthebridgetonowhere]

I'd love to have a go at this. It seems rather straightforward (though I am not too familiar with Typescript). Would the image open in a new page, in a modal box, or it would be like a hide/show div below the query status?