Change so that -B and no -B return sub arrays, now that I've changed the JS code to handle the new format.
Change so that -B and no -B return sub arrays, now that I've changed
the JS code to handle the new format.

Also add a -s (silent option) to avoid warnings that cause needless email
from the Geni XMLRPC interface.

nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome