Should we support async and await?

[donkirkby]

While experimenting with the new features in Python 3.7 for #257, I found that async and await messed up the live coding display, because multiple function calls can get interspersed. See the comments on that issue for detailed examples.

However, is it even helpful to use live coding for asynchronous code? I'm going to wait until I have more experience with it or I hear from users. I wonder if generating some version of a sequence diagram would be more useful.

Brett Cannon wrote a good introduction to async and await.