[Feature] createSchedule should return schedule's Id (#1861)

issue: https://github.com/apache/incubator-dolphinscheduler/issues/1860

dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/SchedulerService.java

@@ -167,6 +167,7 @@ public class SchedulerService extends BaseService {
         processDefinitionMapper.updateById(processDefinition);
         putMsg(result, Status.SUCCESS);
 
+        result.put("scheduleId", scheduleObj.getId());
         return result;
     }