Add missing include

Fixes compilation with gcc 10

Change-Id: I54f0808c7519b8bf1a668f05c4d09d4ca3d3b11f
diff --git a/src/statistics.cpp b/src/statistics.cpp
index f5f5516..2eb6cbe 100644
--- a/src/statistics.cpp
+++ b/src/statistics.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2014-2017,  The University of Memphis,
+/*
+ * Copyright (c) 2014-2020,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -28,13 +28,11 @@
 size_t
 Statistics::get(PacketType type) const
 {
-  std::map<PacketType,int>::const_iterator it = m_packetCounter.find(type);
-  if(it != m_packetCounter.end())
-  {
+  auto it = m_packetCounter.find(type);
+  if (it != m_packetCounter.end()) {
     return it->second;
   }
-  else
-  {
+  else {
     return 0;
   }
 }
@@ -48,8 +46,7 @@
 void
 Statistics::resetAll()
 {
-  for (auto&& it : m_packetCounter )
-  {
+  for (auto& it : m_packetCounter) {
     it.second = 0;
   }
 }
diff --git a/src/statistics.hpp b/src/statistics.hpp
index 435938f..c93b93b 100644
--- a/src/statistics.hpp
+++ b/src/statistics.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2014-2017,  The University of Memphis,
+/*
+ * Copyright (c) 2014-2020,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -23,12 +23,12 @@
 #define NLSR_STATISTICS_HPP
 
 #include <map>
+#include <ostream>
 
 namespace nlsr {
 
 class Statistics
 {
-
 public:
   enum class PacketType {
     SENT_HELLO_INTEREST,
@@ -57,10 +57,10 @@
   get(PacketType) const;
 
   void
-  resetAll();
+  increment(PacketType);
 
   void
-  increment(PacketType);
+  resetAll();
 
   const std::map<PacketType,int>&
   getCounter() const
@@ -69,7 +69,7 @@
   }
 
 private:
-  std::map<PacketType,int> m_packetCounter;
+  std::map<PacketType, int> m_packetCounter;
 };
 
 std::ostream&