Configurable multistream-select protocol. Add V1Lazy variant. (#1245)

Make the multistream-select protocol (version) configurable
on transport upgrades as well as for individual substreams.

Add a "lazy" variant of multistream-select 1.0 that delays
sending of negotiation protocol frames as much as possible
but is only safe to use under additional assumptions that
go beyond what is required by the multistream-select v1
specification.

src/lib.rs

@@ -244,7 +244,7 @@ pub fn build_tcp_ws_secio_mplex_yamux(keypair: identity::Keypair)
     -> impl Transport<Output = (PeerId, impl core::muxing::StreamMuxer<OutboundSubstream = impl Send, Substream = impl Send, Error = impl Into<io::Error>> + Send + Sync), Error = impl error::Error + Send, Listener = impl Send, Dial = impl Send, ListenerUpgrade = impl Send> + Clone
 {
     CommonTransport::new()
-        .upgrade()
+        .upgrade(core::upgrade::Version::V1)
         .authenticate(secio::SecioConfig::new(keypair))
         .multiplex(core::upgrade::SelectUpgrade::new(yamux::Config::default(), mplex::MplexConfig::new()))
         .map(|(peer, muxer), _| (peer, core::muxing::StreamMuxerBox::new(muxer)))