Yuta UEKUSA

Add sort macro

3

- Add sort macro for list - `sortAsc(var, )` - `sortDesc(var, )` - `sortStableAsc(var, )` - `sortStableDesc(var, )` resolve https://github.com/mercari/grpc-federation/issues/173

Support for request hedging

3

**Describe the feature request** Envoy supports [request hedging](https://www.envoyproxy.io/docs/envoy/v1.12.0/intro/arch_overview/http/http_routing.html#arch-overview-http-routing-hedging), which can reduce tail latency, from v1.11.0, but it looks like Istio doesn't support to generate such Envoy configuration. Could this be...