Always build in C++11 mode

refs: #1930

Change-Id: Iedad4a814e5c7e6a5486f2f7e16c45c356131792
diff --git a/nsync/sync-full-leaf.cc b/nsync/sync-full-leaf.cc
index 84f96e3..67c68fc 100644
--- a/nsync/sync-full-leaf.cc
+++ b/nsync/sync-full-leaf.cc
@@ -17,13 +17,10 @@
  *
  * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
  *         Chaoyi Bian <bcy@pku.edu.cn>
- *	   Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ *         Alexander Afanasyev <alexander.afanasyev@ucla.edu>
  */
 
 #include "sync-full-leaf.h"
-#include <boost/ref.hpp>
-
-using namespace boost;
 
 namespace Sync {