AMBARI-4293. Support tolerance level for batched requests based on task status. JSON fix. (swagle)

ambari-server/src/main/java/org/apache/ambari/server/state/scheduler/Schedule.java

@@ -138,6 +138,11 @@ public class Schedule {
     return true;
   }
 
+  /**
+   * Return empty if schedule has non usable fields.
+   * @return
+   */
+  @JsonIgnore
   public boolean isEmpty() {
     return (minutes == null || minutes.isEmpty())
       && (hours == null || hours.isEmpty())