Constructing this tree was harder than necessary.
nw: Create Notebooks.
nw: Close Notebooks.
nw: Show/Hide settings.
nw: Create Block.
nw: Delete Block.
nw: Edit Block.
nw: Eval Markdown.
nw: Eval SQL.
nw: Eval Visual.

Note, we need to fix up purescript-c3 to accept the data on the fly.
Currently doing this in the ffi, very unfun, very unsafe.