test reconnection logic in WebSocketProvider

[heckj]

I just cobbled up a bunch of WebSocket related reconnect-on-error logic, including a backoff mechanism. However, there's not really anything easily set up to "fake" a websocket to allow me to test this outside of some sort of broader integration/live testing scenario.

Go through and see if the logic can be tweaked/updated to allow injecting a fake thing that creates a WebSocketTask equivalent (or something that smells and acts like one), and use it to add tests to verify that the various permutations all work as expected.

• failed on receive()
• failed on send()
• corrupted messages
• disconnect() terminating things correctly