[ndnSIM] PIT stats examples

[Alex Afanasyev]

Hi Flávio,

For the first example, did you change anything in the script?  Especially about this line:
  ndnHelper.SetPit ("ns3::ndn::pit::Persistent::AggregateStats");

I just run an unmodified ndn-simple-with-pit-operation-stats.cc and it didn't not give me any error. I tried on Mac and Linux with the latest versions of NS-3 and ndnSIM.

For the second example. There was an error with the header format.  The scenario actually printed out only 4 parameters: Time, NodeId, NodeName, and NumberOfPitEntries.  I have pushed the correction.

---
Alex

> Hi Alex,
> 
> I ran the PIT stats examples:
> 
> 1)"ndn-simple-with-pit-operation-stats.cc" and printed:
> 
> Time	NodeId	Updates	Inserts	Lookups	Erases
> Invalid PIT class, please correct the scenario
> 
> 2) "ndn-simple-with-pit-count-stats.cc" with
> "Simulator::Schedule (Seconds (0.001), PeriodicStatsPrinter, nodes.Get
> (1), Seconds (0.001));" and not printed Lookups/NumberOfPitEntries
> 
> Time	NodeId	NodeName	Inserts	Lookups	NumberOfPitEntries
> 0.001	1	router	0
> 0.002	1	router	0
> 0.003	1	router	0
> 0.004	1	router	0
> 0.005	1	router	0
> 0.006	1	router	0
> 0.007	1	router	0
> 0.008	1	router	0
> 0.009	1	router	0
> 0.01	1	router	0
> 0.011	1	router	1
> 0.012	1	router	1
> 0.013	1	router	1
> 0.014	1	router	1
> 0.015	1	router	1
> 0.016	1	router	1
> 0.017	1	router	1
> 0.018	1	router	1
> 0.019	1	router	1
> 0.02	1	router	1
> 0.021	1	router	1
> 
> Do you know what is happening?
> Thank you in advance,
> Flávio