Benchmark tests on a random digraph (n = 100000, m = 1000000)

ListDigraph - Building                  0.322121
ListDigraph (sorted arcs) - Building    0.23652
SmartDigraph - Building                 0.11954
SmartDigraph (sorted arcs) - Building   0.10477
StaticDigraph - Building                0.221492

ListDigraph - Iteration
  NodeIt:    0.000797296    	0.000792718
  ArcIt:     0.086327    	0.0863771
  OutArcIt:  0.0819412    	0.0818811
  InArcIt:   0.081785    	0.0818035

ListDigraph (sorted arcs) - Iteration
  NodeIt:    0.000783181    	0.000775409
  ArcIt:     0.0821163    	0.0821648
  OutArcIt:  0.0117887    	0.011823
  InArcIt:   0.0775816    	0.0776839

SmartDigraph - Iteration
  NodeIt:    9.07183e-05    	9.06944e-05
  ArcIt:     0.0009058    	0.00090611
  OutArcIt:  0.0795787    	0.0795342
  InArcIt:   0.0794843    	0.0795057

SmartDigraph (sorted arcs) - Iteration
  NodeIt:    9.07183e-05    	9.06944e-05
  ArcIt:     0.000905991    	0.000905681
  OutArcIt:  0.00836039    	0.00848172
  InArcIt:   0.0751538    	0.0751682

StaticDigraph - Iteration
  NodeIt:    9.06944e-05    	9.06944e-05
  ArcIt:     0.000906205    	0.00090549
  OutArcIt:  0.00279782    	0.0042738
  InArcIt:   0.0603011    	0.060291

