MQTT-SN specification update

A quick update. At the last meeting the SC accepted the resolutions of all but one of the outstanding issues.  I and the other editors are working to incorporate the resolutions into the working draft so that it is ready for the next stage of review.  

The issue list can be found here: https://issues.oasis-open.org/browse/MQTT-580?jql=project%20%3D%20MQTT%20AND%20component%20%3D%20MQTT-SN%20ORDER%20BY%20created%20DESC

I will arrange an SC meeting soon.  Whether we will have all the issue resolutions incorporated by then, I don't know yet.