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-congestion-topo-plugin.cpp b/examples/ndn-congestion-topo-plugin.cpp
index 77069ee..0a6a58b 100644
--- a/examples/ndn-congestion-topo-plugin.cpp
+++ b/examples/ndn-congestion-topo-plugin.cpp
@@ -30,10 +30,10 @@
  *   /------\	                                                 /------\
  *   | Src1 |<--+                                            +-->| Dst1 |
  *   \------/    \                                          /    \------/
- *            	 \                                        /     
- *                 +-->/------\   "bottleneck"  /------\<-+      
- *                     | Rtr1 |<===============>| Rtr2 |         
- *                 +-->\------/                 \------/<-+      
+ *            	 \                                        /
+ *                 +-->/------\   "bottleneck"  /------\<-+
+ *                     | Rtr1 |<===============>| Rtr2 |
+ *                 +-->\------/                 \------/<-+
  *                /                                        \
  *   /------\    /                                          \    /------\
  *   | Src2 |<--+                                            +-->| Dst2 |
@@ -45,68 +45,67 @@
  */
 
 int
-main (int argc, char *argv[])
+main(int argc, char* argv[])
 {
   CommandLine cmd;
-  cmd.Parse (argc, argv);
+  cmd.Parse(argc, argv);
 
-  AnnotatedTopologyReader topologyReader ("", 25);
-  topologyReader.SetFileName ("src/ndnSIM/examples/topologies/topo-6-node.txt");
-  topologyReader.Read ();
+  AnnotatedTopologyReader topologyReader("", 25);
+  topologyReader.SetFileName("src/ndnSIM/examples/topologies/topo-6-node.txt");
+  topologyReader.Read();
 
   // Install NDN stack on all nodes
   ndn::StackHelper ndnHelper;
-  ndnHelper.SetForwardingStrategy ("ns3::ndn::fw::BestRoute");
-  ndnHelper.SetContentStore ("ns3::ndn::cs::Lru",
-                              "MaxSize", "10000");
-  ndnHelper.InstallAll ();
+  ndnHelper.SetForwardingStrategy("ns3::ndn::fw::BestRoute");
+  ndnHelper.SetContentStore("ns3::ndn::cs::Lru", "MaxSize", "10000");
+  ndnHelper.InstallAll();
 
   // Installing global routing interface on all nodes
   ndn::GlobalRoutingHelper ndnGlobalRoutingHelper;
-  ndnGlobalRoutingHelper.InstallAll ();
+  ndnGlobalRoutingHelper.InstallAll();
 
   // Getting containers for the consumer/producer
-  Ptr<Node> consumer1 = Names::Find<Node> ("Src1");
-  Ptr<Node> consumer2 = Names::Find<Node> ("Src2");
+  Ptr<Node> consumer1 = Names::Find<Node>("Src1");
+  Ptr<Node> consumer2 = Names::Find<Node>("Src2");
 
-  Ptr<Node> producer1 = Names::Find<Node> ("Dst1");
-  Ptr<Node> producer2 = Names::Find<Node> ("Dst2");
+  Ptr<Node> producer1 = Names::Find<Node>("Dst1");
+  Ptr<Node> producer2 = Names::Find<Node>("Dst2");
 
-  ndn::AppHelper consumerHelper ("ns3::ndn::ConsumerCbr");
-  consumerHelper.SetAttribute ("Frequency", StringValue ("100")); // 100 interests a second
+  ndn::AppHelper consumerHelper("ns3::ndn::ConsumerCbr");
+  consumerHelper.SetAttribute("Frequency", StringValue("100")); // 100 interests a second
 
   // on the first consumer node install a Consumer application
   // that will express interests in /dst1 namespace
-  consumerHelper.SetPrefix ("/dst1");
-  consumerHelper.Install (consumer1);
+  consumerHelper.SetPrefix("/dst1");
+  consumerHelper.Install(consumer1);
 
   // on the second consumer node install a Consumer application
   // that will express interests in /dst2 namespace
-  consumerHelper.SetPrefix ("/dst2");
-  consumerHelper.Install (consumer2);
-  
-  ndn::AppHelper producerHelper ("ns3::ndn::Producer");
-  producerHelper.SetAttribute ("PayloadSize", StringValue("1024"));  
+  consumerHelper.SetPrefix("/dst2");
+  consumerHelper.Install(consumer2);
+
+  ndn::AppHelper producerHelper("ns3::ndn::Producer");
+  producerHelper.SetAttribute("PayloadSize", StringValue("1024"));
 
   // Register /dst1 prefix with global routing controller and
   // install producer that will satisfy Interests in /dst1 namespace
-  ndnGlobalRoutingHelper.AddOrigins ("/dst1", producer1);
-  producerHelper.SetPrefix ("/dst1");
-  producerHelper.Install (producer1);
+  ndnGlobalRoutingHelper.AddOrigins("/dst1", producer1);
+  producerHelper.SetPrefix("/dst1");
+  producerHelper.Install(producer1);
 
   // Register /dst2 prefix with global routing controller and
   // install producer that will satisfy Interests in /dst2 namespace
-  ndnGlobalRoutingHelper.AddOrigins ("/dst2", producer2);
-  producerHelper.SetPrefix ("/dst2");
-  producerHelper.Install (producer2);
+  ndnGlobalRoutingHelper.AddOrigins("/dst2", producer2);
+  producerHelper.SetPrefix("/dst2");
+  producerHelper.Install(producer2);
 
   // Calculate and install FIBs
-  ndn::GlobalRoutingHelper::CalculateRoutes ();
+  ndn::GlobalRoutingHelper::CalculateRoutes();
 
-  Simulator::Stop (Seconds (20.0));
+  Simulator::Stop(Seconds(20.0));
 
-  Simulator::Run ();
-  Simulator::Destroy ();
+  Simulator::Run();
+  Simulator::Destroy();
 
   return 0;
 }