More robust discovery

Uses `arp-scan` when DHCP fails to give the IP. Pushes live changes to a supervisord.conf file to keep the drivers running, and uses a different port for each one. I temporarily disabled pushing the discovered config files to a git repo and instead deposit them in a local driverconfig folder.

I'll be making other changes in the sMAP core to integrate boss-wave for the OpenBAS project, but I think these changes should be in master.