[#110] Add "h2" as next proto to allow HTTP/2 requests in http.Serve

Signed-off-by: Alex Vanin <a.vanin@yadro.com>

cmd/http-gw/server.go

@@ -74,6 +74,7 @@ func newServer(ctx context.Context, serverInfo ServerInfo) (*server, error) {
 
 		ln = tls.NewListener(ln, &tls.Config{
 			GetCertificate: tlsProvider.GetCertificate,
+			NextProtos:     []string{"h2"}, // required to enable HTTP/2 requests in `http.Serve`
 		})
 	}