Generate static html/pngs of a current workbook

[jsa-aerial]

Save a static snapshot of DOM of a current Saite session. No active visualizations. Tabs and their data would turn into document 'headers' and bodies. So, the result is serialized content of tabs generated from left most tab to right most tab.

As a byproduct of this, all the plots/charts would also be independently saved as accessible pngs.

It is not clear that this all that useful, but various people seem to think it is.

Fortunately, as described in #1, being totally data centric in all presentation aspects makes this more straight forward than might first be thought.