First checkin. Finds fully connected set of nodes. Fully connected

defined (for now) as data exists within 6 hours (code param) in the
past for latency and bw (forward and backward) between all nodes in
the set.


example run:
perl goodnodes.pl -e tbres/pelabbgmon 10
where 10 is the number of nodes to ask for.
The -e option limits the nodes to look at to those listed in that experiment.