build: use C++11

Change-Id: I0e58ac4e9cb42d07a9b58125d761875f91c7744c
Refs: #1930
diff --git a/src/common.hpp b/src/common.hpp
index 317789c..ee122d3 100644
--- a/src/common.hpp
+++ b/src/common.hpp
@@ -43,6 +43,8 @@
 #include <list>
 #include <algorithm>
 #include <iostream>
+#include <functional>
+#include <memory>
 
 namespace repo {
 
@@ -58,13 +60,11 @@
 using ndn::Scheduler;
 using ndn::ValidatorConfig;
 
-using ndn::bind;
-using ndn::shared_ptr;
-using ndn::make_shared;
-using ndn::enable_shared_from_this;
-
-using std::vector;
-using std::string;
+using std::shared_ptr;
+using std::make_shared;
+using std::bind;
+using std::placeholders::_1;
+using std::placeholders::_2;
 
 using boost::noncopyable;