* Make un-graceful shutdown a bit more graceful
- Change how graceful shutdown is done to ensure there are no errors on shutdown.
- Avoid closing pipes from under other components that own those pipes.
- Close the application output so that the application's read loop ends gracefully. For websockets, we cancel the token, for other transports, we close the output directly.
There was a race condition between the first poll and any other http request that was sent.
In particular, if you called StartAsync then StopAsync it was possible for the delete to happen before the poll started leading to 400 errors. This change fixes that by making the very first poll
return immediately so that the client can use that to determine if there was an error connecting.
David Fowler
BrennanConroy
James Newton-King
Andrew Stanton-Nurse