Want to yank some of this into another PR ahead of time, getting files in.

…nd cleanup

In prep for changes to how we handle subscriptions internally, this does several things:
- Upgrades default Redis server assumption to 3.x
- Routes PING on Subscription keepalives over the subscription bridge appropriately
- Fixes cluster sharding from default(RedisKey) to shared logic for RedisChannel as well (both in byte[] form)
- General code cleanup in the area (getting a lot of DEBUG/VERBOSE noise into isolated files)

This is something that tripped me and at least 1 user up - let's save some pain.

This is effectively the behavior we had before (but we are ensured connected now). We just want the count here and to start them, so let's do that also pipelining the `n` commands as we did before instead of awaiting each. We also don't need the `Task` overhead. This makes moving to a variadic command set for this less urgent.