update echo mode to send some data periodically
use one BusObject on gateway side, use two different signals (direction based)
fix the re-connection procedure

need to mark device unregistered to force register procedure later,
also need to unsubscribe old commands...
update destination name on channel changing
update gateway manager script: handle network errors, support detail logs
limit the log file size to 5 MB for bridge and 10MB for gateway
rename wot.io-demo to just devicehive