Merge pull request #130 from Shabirmean/IoTS-1.0.0-M1

"cleanSession" set to true in MQTTTransportHandler

components/device-mgt-iot/org.wso2.carbon.device.mgt.iot/src/main/java/org/wso2/carbon/device/mgt/iot/transport/mqtt/MQTTTransportHandler.java

@@ -133,7 +133,7 @@ public abstract class MQTTTransportHandler
         }
 
         options = new MqttConnectOptions();
-        options.setCleanSession(false);
+        options.setCleanSession(true);
         //TODO:: Use constant strings
         options.setWill(clientWillTopic, "Connection-Lost".getBytes(StandardCharsets.UTF_8), 2,
                         true);