Use the latest `ws`?

It looks like ws is two major revs ahead of what express-ws lists in its dependencies. Perhaps worth moving to it?

[danfuzz]

As with @AuspeXeu I’ve now just dropped my use of this module. In case it helps, here’s the commit in my project that made the change: https://github.com/danfuzz/bayou/pull/466/commits/4ed5569049c138e0e26fb55b1c069e2be8c0a1a6

[danfuzz]

BTW, one thing to watch out for is that my change makes it so that express isn’t involved at all in websocket requests. This means that any route intercepters / middleware you might have installed — notably logging — won’t get invoked.