What would you like to be added?

We currently have a single health endpoint for etcd /health which is used in Kubernetes distros as both liveness and readiness checking. In order to be fully api-compliant, we should have both a liveness check (i.e. /livez) which checks that this individual etcd member is "alive" and does not need to be restarted and a readiness check (i.e. /readyz) which signals that the etcd member is ready to accept traffic.

Why is this needed?

There is a difference between "please restart me I'm that unhealthy" vs "please send me all sorts of traffic, I'm ready for it".