src: Updating code style to conform (more or less) to ndn-cxx style

Also, adding .clang-format that describes the applied style. Note that
this style requires a slightly customized version of clang-format.
diff --git a/examples/ndn-tree-with-l2tracer.cpp b/examples/ndn-tree-with-l2tracer.cpp
index 19ba3a2..8d5e3e0 100644
--- a/examples/ndn-tree-with-l2tracer.cpp
+++ b/examples/ndn-tree-with-l2tracer.cpp
@@ -7,135 +7,135 @@
 using namespace ns3;
 
 int
-main (int argc, char *argv[])
+main(int argc, char* argv[])
 {
   CommandLine cmd;
-  cmd.Parse (argc, argv);
+  cmd.Parse(argc, argv);
 
-  AnnotatedTopologyReader topologyReader ("", 10);
-  topologyReader.SetFileName ("src/ndnSIM/examples/topologies/topo-tree-25-node.txt");
-  topologyReader.Read ();
-  
+  AnnotatedTopologyReader topologyReader("", 10);
+  topologyReader.SetFileName("src/ndnSIM/examples/topologies/topo-tree-25-node.txt");
+  topologyReader.Read();
+
   /****************************************************************************/
   // Install CCNx stack on all nodes
   ndn::StackHelper ccnxHelper;
-  ccnxHelper.SetContentStore ("ns3::ndn::cs::Lru", "MaxSize", "1000");
-  ccnxHelper.SetForwardingStrategy ("ns3::ndn::fw::BestRoute");
-  ccnxHelper.InstallAll ();
+  ccnxHelper.SetContentStore("ns3::ndn::cs::Lru", "MaxSize", "1000");
+  ccnxHelper.SetForwardingStrategy("ns3::ndn::fw::BestRoute");
+  ccnxHelper.InstallAll();
   /****************************************************************************/
   // Installing global routing interface on all nodes
   ndn::GlobalRoutingHelper ccnxGlobalRoutingHelper;
-  ccnxGlobalRoutingHelper.InstallAll ();
+  ccnxGlobalRoutingHelper.InstallAll();
   /****************************************************************************/
   // Getting containers for the consumer/producer
-  Ptr<Node> consumer1 = Names::Find<Node> ("Src1");
-  Ptr<Node> consumer2 = Names::Find<Node> ("Src2");
-  Ptr<Node> consumer3 = Names::Find<Node> ("Src3");
-  Ptr<Node> consumer4 = Names::Find<Node> ("Src4");
-  Ptr<Node> consumer5 = Names::Find<Node> ("Src5");
-  Ptr<Node> consumer6 = Names::Find<Node> ("Src6");
-  Ptr<Node> consumer7 = Names::Find<Node> ("Src7");
-  Ptr<Node> consumer8 = Names::Find<Node> ("Src8");
-  Ptr<Node> consumer9 = Names::Find<Node> ("Src9");
+  Ptr<Node> consumer1 = Names::Find<Node>("Src1");
+  Ptr<Node> consumer2 = Names::Find<Node>("Src2");
+  Ptr<Node> consumer3 = Names::Find<Node>("Src3");
+  Ptr<Node> consumer4 = Names::Find<Node>("Src4");
+  Ptr<Node> consumer5 = Names::Find<Node>("Src5");
+  Ptr<Node> consumer6 = Names::Find<Node>("Src6");
+  Ptr<Node> consumer7 = Names::Find<Node>("Src7");
+  Ptr<Node> consumer8 = Names::Find<Node>("Src8");
+  Ptr<Node> consumer9 = Names::Find<Node>("Src9");
 
-  Ptr<Node> producer1 = Names::Find<Node> ("Dst1");
-  Ptr<Node> producer2 = Names::Find<Node> ("Dst2");
-  Ptr<Node> producer3 = Names::Find<Node> ("Dst3");
-  Ptr<Node> producer4 = Names::Find<Node> ("Dst4");
-  Ptr<Node> producer5 = Names::Find<Node> ("Dst5");
-  Ptr<Node> producer6 = Names::Find<Node> ("Dst6");
-  Ptr<Node> producer7 = Names::Find<Node> ("Dst7");
-  Ptr<Node> producer8 = Names::Find<Node> ("Dst8");
-  Ptr<Node> producer9 = Names::Find<Node> ("Dst9");
+  Ptr<Node> producer1 = Names::Find<Node>("Dst1");
+  Ptr<Node> producer2 = Names::Find<Node>("Dst2");
+  Ptr<Node> producer3 = Names::Find<Node>("Dst3");
+  Ptr<Node> producer4 = Names::Find<Node>("Dst4");
+  Ptr<Node> producer5 = Names::Find<Node>("Dst5");
+  Ptr<Node> producer6 = Names::Find<Node>("Dst6");
+  Ptr<Node> producer7 = Names::Find<Node>("Dst7");
+  Ptr<Node> producer8 = Names::Find<Node>("Dst8");
+  Ptr<Node> producer9 = Names::Find<Node>("Dst9");
   /****************************************************************************/
-  ndn::AppHelper consumerHelper ("ns3::ndn::ConsumerCbr");
-  consumerHelper.SetAttribute ("Frequency", StringValue ("1000"));//interests per Second
-  consumerHelper.SetAttribute ("Randomize", StringValue ("uniform"));
+  ndn::AppHelper consumerHelper("ns3::ndn::ConsumerCbr");
+  consumerHelper.SetAttribute("Frequency", StringValue("1000")); // interests per Second
+  consumerHelper.SetAttribute("Randomize", StringValue("uniform"));
   /****************************************************************************/
   // on the first to ninth consumer node install a Consumer application
   // that will express interests in /dst1 to /dst9 namespace
-  consumerHelper.SetPrefix ("/dst9");
-  consumerHelper.Install (consumer1);
+  consumerHelper.SetPrefix("/dst9");
+  consumerHelper.Install(consumer1);
 
-  consumerHelper.SetPrefix ("/dst8");
-  consumerHelper.Install (consumer2);
+  consumerHelper.SetPrefix("/dst8");
+  consumerHelper.Install(consumer2);
 
-  consumerHelper.SetPrefix ("/dst7");
-  consumerHelper.Install (consumer3);
+  consumerHelper.SetPrefix("/dst7");
+  consumerHelper.Install(consumer3);
 
-  consumerHelper.SetPrefix ("/dst6");
-  consumerHelper.Install (consumer4);
+  consumerHelper.SetPrefix("/dst6");
+  consumerHelper.Install(consumer4);
 
-  consumerHelper.SetPrefix ("/dst5");
-  consumerHelper.Install (consumer5);
+  consumerHelper.SetPrefix("/dst5");
+  consumerHelper.Install(consumer5);
 
-  consumerHelper.SetPrefix ("/dst4");
-  consumerHelper.Install (consumer6);
+  consumerHelper.SetPrefix("/dst4");
+  consumerHelper.Install(consumer6);
 
-  consumerHelper.SetPrefix ("/dst3");
-  consumerHelper.Install (consumer7);
+  consumerHelper.SetPrefix("/dst3");
+  consumerHelper.Install(consumer7);
 
-  consumerHelper.SetPrefix ("/dst2");
-  consumerHelper.Install (consumer8);
+  consumerHelper.SetPrefix("/dst2");
+  consumerHelper.Install(consumer8);
 
-  consumerHelper.SetPrefix ("/dst1");
-  consumerHelper.Install (consumer9);
-  
+  consumerHelper.SetPrefix("/dst1");
+  consumerHelper.Install(consumer9);
+
   /****************************************************************************/
-  ndn::AppHelper producerHelper ("ns3::ndn::Producer");
-  producerHelper.SetAttribute ("PayloadSize", StringValue("1024"));
+  ndn::AppHelper producerHelper("ns3::ndn::Producer");
+  producerHelper.SetAttribute("PayloadSize", StringValue("1024"));
   /****************************************************************************/
   // Register /dst1 to /dst9 prefix with global routing controller and
   // install producer that will satisfy Interests in /dst1 to /dst9 namespace
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst1", producer1);
-  producerHelper.SetPrefix ("/dst1");
-  producerHelper.Install (producer1);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst1", producer1);
+  producerHelper.SetPrefix("/dst1");
+  producerHelper.Install(producer1);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst2", producer2);
-  producerHelper.SetPrefix ("/dst2");
-  producerHelper.Install (producer2);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst2", producer2);
+  producerHelper.SetPrefix("/dst2");
+  producerHelper.Install(producer2);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst3", producer3);
-  producerHelper.SetPrefix ("/dst3");
-  producerHelper.Install (producer3);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst3", producer3);
+  producerHelper.SetPrefix("/dst3");
+  producerHelper.Install(producer3);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst4", producer4);
-  producerHelper.SetPrefix ("/dst4");
-  producerHelper.Install (producer4);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst4", producer4);
+  producerHelper.SetPrefix("/dst4");
+  producerHelper.Install(producer4);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst5", producer5);
-  producerHelper.SetPrefix ("/dst5");
-  producerHelper.Install (producer5);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst5", producer5);
+  producerHelper.SetPrefix("/dst5");
+  producerHelper.Install(producer5);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst6", producer6);
-  producerHelper.SetPrefix ("/dst6");
-  producerHelper.Install (producer6);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst6", producer6);
+  producerHelper.SetPrefix("/dst6");
+  producerHelper.Install(producer6);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst7", producer7);
-  producerHelper.SetPrefix ("/dst7");
-  producerHelper.Install (producer7);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst7", producer7);
+  producerHelper.SetPrefix("/dst7");
+  producerHelper.Install(producer7);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst8", producer8);
-  producerHelper.SetPrefix ("/dst8");
-  producerHelper.Install (producer8);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst8", producer8);
+  producerHelper.SetPrefix("/dst8");
+  producerHelper.Install(producer8);
 
-  ccnxGlobalRoutingHelper.AddOrigins ("/dst9", producer9);
-  producerHelper.SetPrefix ("/dst9");
-  producerHelper.Install (producer9);
+  ccnxGlobalRoutingHelper.AddOrigins("/dst9", producer9);
+  producerHelper.SetPrefix("/dst9");
+  producerHelper.Install(producer9);
 
   /*****************************************************************************/
   // Calculate and install FIBs
-  ccnxGlobalRoutingHelper.CalculateRoutes ();
+  ccnxGlobalRoutingHelper.CalculateRoutes();
 
-  Simulator::Stop (Seconds (10.0));
+  Simulator::Stop(Seconds(10.0));
 
   /****************************************************************************/
-  //Tracer:
+  // Tracer:
 
-  L2RateTracer::InstallAll ("drop-trace.txt", Seconds (0.5));
+  L2RateTracer::InstallAll("drop-trace.txt", Seconds(0.5));
 
-  Simulator::Run ();
-  Simulator::Destroy ();
+  Simulator::Run();
+  Simulator::Destroy();
 
   return 0;
 }