Support for adding nonces for CSP?

[andrewk11]

Is there any support/intended support for adding nonces to comply with CSP or using stylesheet-based styles for chart tooltips? I'm working on a project that uses Vega Lite tooltips, and the tooltip inline styling has failed to apply since we required nonces for inline styling.

[domoritz]

I think these would be good improvements but I probably won't have time to implement it myself. Happy to review changes, though.