Cron implemented

src/AItem.ts

@@ -12,6 +12,10 @@ export interface HasStateAndFeedbackTopic extends HasStateTopic {
     getStateFeedbackTopic() : string
 }
 
+export interface HasInTopic {
+    getInTopic() : string
+}
+
 export abstract class AItem {
     protected topicFirstPart: string
     protected itemId: string