Tighten security on UHK BBB gateways.
Updates for newer generation of Beaglebones; fix un-sudoed call to
Trim back to minimal services running on UHK gateway hosts.
Don't start up as many services on beaglebones --- keep it minimal.
Don't use an ancient commit of the Michigan code (but it isn't clear
that HEAD is stable, so gw_commit may need to be tweaked).
Tweak mosquitto logging level for BBB.
Arrange to limit mosquitto daemon logging by default to avoid having
small disks on BBB fill up.
Allow for pulling old version of Michigan code (to avoid the bleeding
Changes for making the UHK gateway code portable to Swarm Boxes.
Rename setup-uhb-gateway.sh to match conventional nomenclature.