src: Another round of source updates: moving all headers close to implementation files

Change-Id: I3d47076504950e67746174623c75383948e9d93d
diff --git a/src/security/certificate-extension.cpp b/src/security/certificate-extension.cpp
index 81d7d34..4864a6b 100644
--- a/src/security/certificate-extension.cpp
+++ b/src/security/certificate-extension.cpp
@@ -18,7 +18,7 @@
 #pragma GCC diagnostic ignored "-Wunused-function"
 #endif
 
-#include <ndn-cpp-dev/security/certificate-extension.hpp>
+#include "security/certificate-extension.hpp"
 #include <cryptopp/asn.h>
 
 using namespace std;