public class DefaultSearchClusterRegistrar
Responsible only for registering the default SearchCluster based on default parameters in the config file, if it
doesn't already exist.
All of its work is done at startup via the @WhenReady.
If you need a reference to the default search cluster and need to ensure that it's already been created, you can
inject this in a method annotated with @WhenReady, then use getDefaultSearchCluster.