feat(server): support HTTP1 and HTTP2 automatically

If an HTTP/1 connection has a parse error, but it starts with the HTTP2 preface, converts the connection automatically into an HTTP2 server connection.

Closes #1486

src/server/mod.rs

@@ -50,6 +50,7 @@
 
 pub mod conn;
 #[cfg(feature = "runtime")] mod tcp;
+mod rewind;
 
 use std::fmt;
 #[cfg(feature = "runtime")] use std::net::SocketAddr;