- Renamed KestrelHttpParser to HttpParser
- Removed the generic virtual dispatch as it turns out to be an
order of magnitude slower than regular virtual dispatch. This change
means we also lose the inlining of Frame.OnStartLine and Frame.OnHeader.
- Put everything in the libuv transport package under `Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.*` namespaces.
- Move stuff in Transport.Libuv/Internal/Http and Transport.Libuv/Internal/Infrastructure to Transport.Libuv/Internal (keep the Networking directory for the libuv wrappers).
- Add `Libuv` prefix to most libuv internal classes.
- Rename `KestrelEngine` to `LibuvTransport`.
- Rename `SocketOutputConsumer` to `LibuvOutputConsumer`.
- Rename `SocketOutputProducer` to `OutputProducer`.
- Fix namespaces in `Microsoft.AspNetCore.Server.Kestrel.Core.`