Shuffle the list of secure etcd endpoints if the client fails to connect to first endpoints.
Shuffle the list of secure etcd endpoints if the client fails to connect to first endpoints.

- ETCD client has a bug in its failover/connection code where it fails to connect a secure etcd cluster
  if the first endpoint is down.

- The change is to shuffle the list of endpoints and try connecting again. This is done regardless of
  what error is returned when connecting for the first time.

- Not doing this for non-secure etcd, as this is already handled by the etcd client.

- ETCD has fixed this problem in the recent releases, but that involves changing grpc dependencies. Hence
  this is a stop gap solution.

Known issue: All the watches exit if the first endpoint goes down.

portworx/kvdb