MQTT Perf Enhancments, changing logging in the MQTT library, Renaming QueueDeliveryWorker to MessageFlusher
Merge pull request #163 from pamod/mqtt_dev

MQTT Perf Enhancments, changing logging in the MQTT library, Renaming Qu...
Refactor code and fix a spelling mistake
Merge pull request #165 from a5anka/refactor

Refactor code and fix a spelling mistake