* Extract the NWConnection code into StateManagedNWConnectionChannel
* Process cory's feedback
* Remove dead code whose functionality is already handled by the helper protocol
* Make the address cache non-locked, because its lock has been moved to the accessors
* Move getting the Multipath option into the TCP channel, re-introduce the underscores to the addressCache properties
* Drop the umbrella import
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Co-authored-by: Cory Benfield <lukasa@apple.com>
Joannis Orlandos