Always build in C++11 mode

refs: #1930

Change-Id: Iedad4a814e5c7e6a5486f2f7e16c45c356131792
diff --git a/src/nlsr.hpp b/src/nlsr.hpp
index 866ad7c..de6f061 100644
--- a/src/nlsr.hpp
+++ b/src/nlsr.hpp
@@ -33,6 +33,7 @@
 #include <ndn-cxx/management/nfd-face-event-notification.hpp>
 #include <ndn-cxx/management/nfd-face-monitor.hpp>
 
+#include "common.hpp"
 #include "conf-parameter.hpp"
 #include "adjacency-list.hpp"
 #include "name-prefix-list.hpp"