security: Add doxygen comments

Change-Id: Ieafe4d13513e626d84ef9e621694f69844785018
diff --git a/src/security/sec-public-info-memory.hpp b/src/security/sec-public-info-memory.hpp
index e598ebf..04104ea 100644
--- a/src/security/sec-public-info-memory.hpp
+++ b/src/security/sec-public-info-memory.hpp
@@ -5,8 +5,8 @@
  * See COPYING for copyright and distribution information.
  */
 
-#ifndef NDN_SEC_PUBLIC_INFO_MEMORY_HPP
-#define NDN_SEC_PUBLIC_INFO_MEMORY_HPP
+#ifndef NDN_SECURITY_SEC_PUBLIC_INFO_MEMORY_HPP
+#define NDN_SECURITY_SEC_PUBLIC_INFO_MEMORY_HPP
 
 #include "../common.hpp"
 #include "sec-public-info.hpp"
@@ -232,6 +232,6 @@
   CertificateStore certificateStore_;                    
 };
 
-}
+} // namespace ndn
 
-#endif
+#endif //NDN_SECURITY_SEC_PUBLIC_INFO_MEMORY_HPP