A means of accessing reusable clients.
Createa a client which will send requests to the given locations.
Createa a client which will send requests to the given locations.
If the iterable contains a single entry, then the RestClient will be a whatever the cached client returns for that location.
If multiple locations are specified, then it will be a RoundRobinClient which sends requests in turn to each location.
a RestClient for the given locations