Swap robust-websocket for reconnecting-websocket

[Terkwood]

Let's try switching our current websocket wrapper (github)(npm) for one that's popular (github) (npm).

I doubt this library is causing the issue in #513, but it wouldn't hurt to rule this out.

[Terkwood]

This issue is a shot in the dark. But if you do follow this path, try reproducing the Dead Net dialog using an instance running in US Azure. You can compare the results across the two libs