Normalizing namespace usage (ndnSIM namespace is now always under ns3)
diff --git a/utils/empty-policy.h b/utils/empty-policy.h
index a04507d..04bc676 100644
--- a/utils/empty-policy.h
+++ b/utils/empty-policy.h
@@ -21,6 +21,8 @@
 #ifndef EMPTY_POLICY_H_
 #define EMPTY_POLICY_H_
 
+namespace ns3
+{
 namespace ndnSIM
 {
 
@@ -51,6 +53,7 @@
   };
 };
 
-}
+} // ndnSIM
+} // ns3
 
 #endif // EMPTY_POLICY_H_