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/model/ndn-net-device-face.cpp b/model/ndn-net-device-face.cpp
index af4baa0..31d57fc 100644
--- a/model/ndn-net-device-face.cpp
+++ b/model/ndn-net-device-face.cpp
@@ -33,20 +33,17 @@
 #include "ns3/channel.h"
 #include "ns3/ndn-name.hpp"
 
-NS_LOG_COMPONENT_DEFINE ("ndn.NetDeviceFace");
+NS_LOG_COMPONENT_DEFINE("ndn.NetDeviceFace");
 
 namespace ns3 {
 namespace ndn {
 
-NS_OBJECT_ENSURE_REGISTERED (NetDeviceFace);
+NS_OBJECT_ENSURE_REGISTERED(NetDeviceFace);
 
 TypeId
-NetDeviceFace::GetTypeId ()
+NetDeviceFace::GetTypeId()
 {
-  static TypeId tid = TypeId ("ns3::ndn::NetDeviceFace")
-    .SetParent<Face> ()
-    .SetGroupName ("Ndn")
-    ;
+  static TypeId tid = TypeId("ns3::ndn::NetDeviceFace").SetParent<Face>().SetGroupName("Ndn");
   return tid;
 }
 
@@ -54,20 +51,20 @@
  * By default, Ndn face are created in the "down" state.  Before
  * becoming useable, the user must invoke SetUp on the face
  */
-NetDeviceFace::NetDeviceFace (Ptr<Node> node, const Ptr<NetDevice> &netDevice)
-  : Face (node)
-  , m_netDevice (netDevice)
+NetDeviceFace::NetDeviceFace(Ptr<Node> node, const Ptr<NetDevice>& netDevice)
+  : Face(node)
+  , m_netDevice(netDevice)
 {
-  NS_LOG_FUNCTION (this << netDevice);
+  NS_LOG_FUNCTION(this << netDevice);
 
-  SetMetric (1); // default metric
+  SetMetric(1); // default metric
 
-  NS_ASSERT_MSG (m_netDevice != 0, "NetDeviceFace needs to be assigned a valid NetDevice");
+  NS_ASSERT_MSG(m_netDevice != 0, "NetDeviceFace needs to be assigned a valid NetDevice");
 }
 
-NetDeviceFace::~NetDeviceFace ()
+NetDeviceFace::~NetDeviceFace()
 {
-  NS_LOG_FUNCTION_NOARGS ();
+  NS_LOG_FUNCTION_NOARGS();
 }
 
 NetDeviceFace& NetDeviceFace::operator= (const NetDeviceFace &)
@@ -76,84 +73,85 @@
 }
 
 Ptr<NetDevice>
-NetDeviceFace::GetNetDevice () const
+NetDeviceFace::GetNetDevice() const
 {
   return m_netDevice;
 }
 
 void
-NetDeviceFace::RegisterProtocolHandlers (const InterestHandler &interestHandler, const DataHandler &dataHandler)
+NetDeviceFace::RegisterProtocolHandlers(const InterestHandler& interestHandler,
+                                        const DataHandler& dataHandler)
 {
-  NS_LOG_FUNCTION (this);
+  NS_LOG_FUNCTION(this);
 
-  Face::RegisterProtocolHandlers (interestHandler, dataHandler);
+  Face::RegisterProtocolHandlers(interestHandler, dataHandler);
 
-  m_node->RegisterProtocolHandler (MakeCallback (&NetDeviceFace::ReceiveFromNetDevice, this),
-                                   L3Protocol::ETHERNET_FRAME_TYPE, m_netDevice, true/*promiscuous mode*/);
+  m_node->RegisterProtocolHandler(MakeCallback(&NetDeviceFace::ReceiveFromNetDevice, this),
+                                  L3Protocol::ETHERNET_FRAME_TYPE, m_netDevice,
+                                  true /*promiscuous mode*/);
 }
 
 void
-NetDeviceFace:: UnRegisterProtocolHandlers ()
+NetDeviceFace::UnRegisterProtocolHandlers()
 {
-  m_node->UnregisterProtocolHandler (MakeCallback (&NetDeviceFace::ReceiveFromNetDevice, this));
-  Face::UnRegisterProtocolHandlers ();
+  m_node->UnregisterProtocolHandler(MakeCallback(&NetDeviceFace::ReceiveFromNetDevice, this));
+  Face::UnRegisterProtocolHandlers();
 }
 
 bool
-NetDeviceFace::Send (Ptr<Packet> packet)
+NetDeviceFace::Send(Ptr<Packet> packet)
 {
-  if (!Face::Send (packet))
-    {
-      return false;
-    }
-  
-  NS_LOG_FUNCTION (this << packet);
+  if (!Face::Send(packet)) {
+    return false;
+  }
 
-  NS_ASSERT_MSG (packet->GetSize () <= m_netDevice->GetMtu (),
-                 "Packet size " << packet->GetSize () << " exceeds device MTU "
-                 << m_netDevice->GetMtu ()
-                 << " for Ndn; fragmentation not supported");
+  NS_LOG_FUNCTION(this << packet);
 
-  bool ok = m_netDevice->Send (packet, m_netDevice->GetBroadcast (),
-                               L3Protocol::ETHERNET_FRAME_TYPE);
+  NS_ASSERT_MSG(packet->GetSize() <= m_netDevice->GetMtu(),
+                "Packet size " << packet->GetSize() << " exceeds device MTU "
+                               << m_netDevice->GetMtu() << " for Ndn; fragmentation not supported");
+
+  bool ok = m_netDevice->Send(packet, m_netDevice->GetBroadcast(), L3Protocol::ETHERNET_FRAME_TYPE);
   return ok;
 }
 
 // callback
 void
-NetDeviceFace::ReceiveFromNetDevice (Ptr<NetDevice> device,
-                                     Ptr<const Packet> p,
-                                     uint16_t protocol,
-                                     const Address &from,
-                                     const Address &to,
-                                     NetDevice::PacketType packetType)
+NetDeviceFace::ReceiveFromNetDevice(Ptr<NetDevice> device, Ptr<const Packet> p, uint16_t protocol,
+                                    const Address& from, const Address& to,
+                                    NetDevice::PacketType packetType)
 {
-  NS_LOG_FUNCTION (device << p << protocol << from << to << packetType);
-  Receive (p);
+  NS_LOG_FUNCTION(device << p << protocol << from << to << packetType);
+  Receive(p);
 }
 
-
 std::ostream&
-NetDeviceFace::Print (std::ostream& os) const
+NetDeviceFace::Print(std::ostream& os) const
 {
 #ifdef NS3_LOG_ENABLE
-  os << "dev[" << GetNode ()->GetId () << "]=net(" << GetId ();
+  os << "dev[" << GetNode()->GetId() << "]=net(" << GetId();
 
-  if (DynamicCast<PointToPointNetDevice> (m_netDevice))
-    {
-      // extra debugging information which available ONLY for PointToPointNetDevice's
-      os << ",";
-      os << DynamicCast<PointToPointNetDevice> (m_netDevice)->GetChannel ()->GetDevice (0)->GetNode ()->GetId ();
-      os << "-";
-      os << DynamicCast<PointToPointNetDevice> (m_netDevice)->GetChannel ()->GetDevice (1)->GetNode ()->GetId ();
-    }
+  if (DynamicCast<PointToPointNetDevice>(m_netDevice)) {
+    // extra debugging information which available ONLY for PointToPointNetDevice's
+    os << ",";
+    os << DynamicCast<PointToPointNetDevice>(m_netDevice)
+            ->GetChannel()
+            ->GetDevice(0)
+            ->GetNode()
+            ->GetId();
+    os << "-";
+    os << DynamicCast<PointToPointNetDevice>(m_netDevice)
+            ->GetChannel()
+            ->GetDevice(1)
+            ->GetNode()
+            ->GetId();
+  }
   os << ")";
 #else
-  os << "dev=net(" << GetId () << ")";
+  os << "dev=net(" << GetId() << ")";
 #endif
   return os;
 }
 
 } // namespace ndnsim
 } // namespace ns3
-