Turbo color scale

[nicolaskruchten]

@empet kindly made a Plotly-formatted scale here https://community.plotly.com/t/new-google-ai-turbo-colorscale/42627/3 so it'll be trivial to add it into our color list.

[nicolaskruchten]

See https://ai.googleblog.com/2019/08/turbo-improved-rainbow-colormap-for.html