Added additonal tracing for Redis
Invert logic to raise long polling reconnects on the server

- Checking for "/poll" to suppress reconnects does not work since 1.0.*
  clients do not append anything to the URL of poll requests.
- Raising reconnects only  for long polling requests ending with
  "/reconnect" preserves the old server behavior
- This prevents 1.0.* clients from causing a reconnect per poll

#3044
Merge branch 'release' into dev
Added new Redis tracing
Create PreserveCulture extension method for use with async/await
Use PreserveCulture for all awaits
LostInReconnection - when the client successfully reconnected it did not clear the TimedOut/HasBeenWarned flags which could result in never invoking the LostConnection/OnConnectionSlow methods if a new timeout happened immediately after reconnecting because we would use stale values set before the reconnection happened (i.e. the client would "think" it already invoked the LostConnection/OnConnectionSlow method after reconnecting whereas it actually did not). Fixes #3046.