We previously `join`ed on piping data from both sides, meaning
that the future didn't complete until **both** sides had disconnected.
Even if the client disconnected, it was possible the server never knew,
and we "leaked" this future.
To fix this, the `join` is replaced with a `Duplex` future, which pipes
from both ends into the other, while also detecting when one side shuts
down. When a side does shutdown, a write shutdown is forwarded to the
other side, to allow draining to occur for deployments that half-close
sockets.
Closes#434
The proxy will now try to detect what protocol new connections are
using, and route them accordingly. Specifically:
- HTTP/2 stays the same.
- HTTP/1 is now accepted, and will try to send an HTTP/1 request
to the target.
- If neither HTTP/1 nor 2, assume a TCP stream and simply forward
between the source and destination.
* tower-h2: fix Server Clone bounds
* proxy: implement Async{Read,Write} extra methods for Connection
Closes#130Closes#131
Sean McArthur