* Decouple connection objects from the server (#2535)
- Making progress towards being able to use the connection objects on the client side.
* Wait for input writer to complete before calling OnConnectionClosed (#2566)
* Wait for the ConnectionClosed token to stop tracking connections (#2574)
- The prior strategy of waiting for the pipe completed callbacks doesn't work
because blocks are returned to the memory pool after the callbacks are fired.
* Consistently handle connection resets (#2547)
* Provide better connection abort exceptions and logs
* void IConnectionDispatcher.OnConnection
- Made TransportConnecton derive from ConnectionContext
- Less objects, less opinions about what the ConnectionContext is. This diverges from what we do with HttpContext but it seems better overall.
- Made DefaultConnectionContext
- Usable for unit testing
- Usable for benchmarking
* Renames from API review
- Rename Microsoft.AspNetCore.Protocols.Abstractions to Microsoft.AspNetCore.Connections.Abstractions.
- Renamed IConnectionHandler to IConnectionDispatcher (and related properties and types)
- Added ConnectionHandler and UseConnectionHandler extension method to Connections.Abstractions.
- Use ActivatorUtilties to create the ConnectionHandler