ShowDemands - Shows the demands of a net using Metanet or Scigraph
ShowDemands shows the demands of NetList that their volume is between dmin and dmax. All the demands are shown if nothing is indicated)
%net=TrafficExample('Steenbrink');
ShowDemands() // Shows the net
ShowDemands('all','between',100,200)
ShowDemands('used','between',100,200)
// Shows the net with the demands between 100 and 200,
// and the used nodes.
ShowDemands('used',[1 3 8 12],100,200)
// Shows the given demands with values between 100 and 200