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/helper/ndn-app-helper.hpp b/helper/ndn-app-helper.hpp
index e559260..63fa705 100644
--- a/helper/ndn-app-helper.hpp
+++ b/helper/ndn-app-helper.hpp
@@ -35,69 +35,72 @@
  * \brief A helper to make it easier to instantiate an ns3::NdnConsumer Application
  * on a set of nodes.
  */
-class AppHelper
-{        
+class AppHelper {
 public:
-
   /**
    * \brief Create an NdnAppHelper to make it easier to work with Ndn apps
    *
    * \param app Class of the application
    */
-  AppHelper (const std::string &prefix);
+  AppHelper(const std::string& prefix);
 
   /**
    * @brief Set the prefix consumer will be requesting
    */
   void
-  SetPrefix (const std::string &prefix);
-  
+  SetPrefix(const std::string& prefix);
+
   /**
    * \brief Helper function used to set the underlying application attributes.
    *
    * \param name the name of the application attribute to set
    * \param value the value of the application attribute to set
    */
-  void SetAttribute (std::string name, const AttributeValue &value);
-        
+  void
+  SetAttribute(std::string name, const AttributeValue& value);
+
   /**
    * Install an ns3::NdnConsumer on each node of the input container
    * configured with all the attributes set with SetAttribute.
    *
-   * \param c NodeContainer of the set of nodes on which an NdnConsumer 
+   * \param c NodeContainer of the set of nodes on which an NdnConsumer
    * will be installed.
    * \returns Container of Ptr to the applications installed.
    */
-  ApplicationContainer Install (NodeContainer c);
-        
+  ApplicationContainer
+  Install(NodeContainer c);
+
   /**
-   * Install an ns3::NdnConsumer on the node configured with all the 
+   * Install an ns3::NdnConsumer on the node configured with all the
    * attributes set with SetAttribute.
    *
    * \param node The node on which an NdnConsumer will be installed.
    * \returns Container of Ptr to the applications installed.
    */
-  ApplicationContainer Install (Ptr<Node> node);
-        
+  ApplicationContainer
+  Install(Ptr<Node> node);
+
   /**
-   * Install an ns3::NdnConsumer on the node configured with all the 
+   * Install an ns3::NdnConsumer on the node configured with all the
    * attributes set with SetAttribute.
    *
    * \param nodeName The node on which an NdnConsumer will be installed.
    * \returns Container of Ptr to the applications installed.
    */
-  ApplicationContainer Install (std::string nodeName);
-        
+  ApplicationContainer
+  Install(std::string nodeName);
+
 private:
   /**
    * \internal
-   * Install an ns3::NdnConsumer on the node configured with all the 
+   * Install an ns3::NdnConsumer on the node configured with all the
    * attributes set with SetAttribute.
    *
    * \param node The node on which an NdnConsumer will be installed.
    * \returns Ptr to the application installed.
    */
-  Ptr<Application> InstallPriv (Ptr<Node> node);
+  Ptr<Application>
+  InstallPriv(Ptr<Node> node);
   ObjectFactory m_factory;
 };
 
@@ -105,4 +108,3 @@
 } // namespace ns3
 
 #endif // NDN_APP_HELPER_H
-