Here I have a sketchy but functional framework for dealing with
all of the async stuff that a tutorial requires, and an early
draft of what such a tutorial might look like.
I could probably go and remove the first-run message, but I'll
keep it around for now in the unlikely event that something I
haven't anticipated goes wrong in starting up the tutorial.
(imported from commit de9779a66a1b3fe790082decb324c90ec180b39b)
