protected void addHttp2MetricsHandlers(ChannelPipeline pipeline) {
        pipeline.addLast("h2_metrics_inbound", http2MetricsChannelHandlers.inbound());
        pipeline.addLast("h2_metrics_outbound", http2MetricsChannelHandlers.outbound());
    }
TODO - can this be done when we create the Http2StreamChannelBootstrap instead now?
zuul-core/src/main/java/com/netflix/zuul/netty/server/http2/Http2StreamInitializer.java