MQTT-client Message Types Supported

MQTT Mssage Type	Associated Function	Associated Callback Type (set via `MQTTc_ConnSetParam()`)
CONNECT CONNACK	`MQTTc_Connect()`	`MQTTc_PARAM_TYPE_CALLBACK_ON_CONNECT_CMPL`
PUBLISH (to server) PUBACK PUBREC PUBREL PUBCOMP	`MQTTc_Publish()`	`MQTTc_PARAM_TYPE_CALLBACK_ON_PUBLISH_CMPL`
PUBLISH (from server) PUBACK PUBREC PUBREL PUBCOMP	`None, waiting on server.`	`MQTTc_PARAM_TYPE_CALLBACK_ON_PUBLISH_RX`
SUBSCRIBE SUBACK	`MQTTc_Subscribe(),` `MQTTc_SubscribeMult()`	`MQTTc_PARAM_TYPE_CALLBACK_ON_SUBSCRIBE_CMPL`
UNSUBSCRIBE UNSUBACK	`MQTTc_Unsubscribe(),` `MQTTc_UnsubscribeMult()`	`MQTTc_PARAM_TYPE_CALLBACK_ON_UNSUBSCRIBE_CMPL`
PINGREQ PINGRESP	`MQTTc_PingReq()`	`MQTTc_PARAM_TYPE_CALLBACK_ON_PINGREQ_CMPL`
DISCONNECT	`MQTTc_Disconnect()`	`MQTTc_PARAM_TYPE_CALLBACK_ON_DISCONNECT_CMPL`