Feature: max-height for use with virtual in lieu of height

[jclark-dot-org]

using virtual and height: 400 options is great when I have a large JSON string to display, but when the JSON is smaller, I end up with a blank area below my formatted JSON, since I don't need a scroll bar to display the full rendered JSON. Could we add a max-height prop that uses the CSS property max-height instead of height in the rendered component? This would allow it to take up less room, when small, but still be bound when large.