public static void init(Clusters clusters, int operationsRetryAttempts) {
    s_clusters = clusters;
    RetryHelper.operationsRetryAttempts = operationsRetryAttempts;
  }
Provides utility methods to support operations retry
TODO injection as Guice singleon, static for now to avoid major modifications
ambari-server/src/main/java/org/apache/ambari/server/utils/RetryHelper.java