Added timestamp support to heartbeat for removing stale messages

Fixed minor bugs introduced due to code streamlining

Added internal message API descriptions

UID of worker nodes has been changed to IP, streamlined DM code base

initial move complete for internal pub/sub to Kafka - needs testing

started listener for kafka node in dispatcher, but not working correctly

Issue with file server remains, unable to download file from master node

Issue with file server remains, unable to download file from master node

adding setup for multi-host deployment. Added comms via MQTT. Container deployment broken