first commit
added int_to_msg_type
mqtt_async connects ok, but seems to block on get_packets
ping working now
subscribe working
code cleanup and process_publish_pkt added
moved process_publish_pkt inside of connect_to_broker
forgot to add test_mqtt.ml
README -> README.md
Merge branch 'master' of https://github.com/philtomson/mqtt_client

Conflicts:
	README.md