Seaside 3.6 breaks Plotlyjs

[timrowledge]

The javascript rendering changes for Seaside 3.6 broke the PlotlyObject rendering.

[timrowledge]

Here is a working fix; probably could be made prettier.

PlotlySeaside3-6.cs

[timrowledge]

Apologies for not doing the whole git dance. It's just so painful for two tiny methods