code: public static Map<String, List<String>> groupAsgNamesByClusterName(List<String> asgNames) {
          return groupByClusterName(asgNames, new AsgNameProvider<String>() {
              public String extractAsgName(String asgName) {
                  return asgName;
              }
          });
      }
docs: Groups a list of ASG names by cluster name.
  
  @param asgNames list of asg names
  @return map of cluster name to list of ASG names in that cluster