Change #include style

Header files are now always included with their path from the
project's root directory rather than the path relative to
the includer.

Change-Id: If39b8510eef8da00baf5fe88337c45dbdf8c766e
Refs: #3084
diff --git a/tests/identity-management-fixture.cpp b/tests/identity-management-fixture.cpp
index 79d5eb2..781b2a1 100644
--- a/tests/identity-management-fixture.cpp
+++ b/tests/identity-management-fixture.cpp
@@ -19,9 +19,10 @@
  * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
  */
 
-#include "identity-management-fixture.hpp"
-#include "util/io.hpp"
-#include "security/v2/additional-description.hpp"
+#include "tests/identity-management-fixture.hpp"
+
+#include "ndn-cxx/security/v2/additional-description.hpp"
+#include "ndn-cxx/util/io.hpp"
 
 #include <boost/filesystem.hpp>