common: deprecate ndn::ptr_lib and ndn::func_lib

refs #2095

Change-Id: Ia0db9cbea488fa2c52f2c83873167c584d1f40f1
diff --git a/src/common.hpp b/src/common.hpp
index 44a0dd8..0987cf2 100644
--- a/src/common.hpp
+++ b/src/common.hpp
@@ -66,7 +66,14 @@
 
 const size_t MAX_NDN_PACKET_SIZE = 8800;
 
+/** \brief the namespace contains smart pointers
+ *  \deprecated use std:: directly
+ */
 namespace ptr_lib = std;
+
+/** \brief the namespace contains function and bind
+ *  \deprecated use std:: directly
+ */
 namespace func_lib = std;
 
 using std::shared_ptr;