tmp (wokkel): fixes RSM when maxItems is 0

src/tmp/wokkel/rsm.py

@@ -316,7 +316,7 @@ class PubSubClient(pubsub.PubSubClient):
         request = PubSubRequest('items')  # that's a rsm.PubSubRequest instance
         request.recipient = service
         request.nodeIdentifier = nodeIdentifier
-        if maxItems:
+        if maxItems is not None:
             request.maxItems = str(int(maxItems))
         request.subscriptionIdentifier = subscriptionIdentifier
         request.sender = sender