Intake support in hvplot.explorer

[martindurant]

Please produce a method on hvplot.explorer which produces an intake plot spec for the current view, or adds it to a catalog entry. Also, it would be really nice if this were the default viz for dataframe type datasets - but perhaps that's on us.

Note that the concept of capturing plotting commands and inserting them into the corresponding catalog entry's definition was already implemented.

[jbednar]

That all sounds great, and indeed, I'd think it's up to Intake to make that the default view once it's possible to access the plot spec.