security: Convert ValidatorConfig to ValidationPolicyConfig

The security API also provides a convenience ValidatorConfig helper.

Change-Id: Ic86dec4904b917361cb4740204de4b6710d2a386
Refs: #3920
diff --git a/tests/unit-tests/util/placeholders.t.cpp b/tests/unit-tests/util/placeholders.t.cpp
index 032b088..64c1dbf 100644
--- a/tests/unit-tests/util/placeholders.t.cpp
+++ b/tests/unit-tests/util/placeholders.t.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2013-2015 Regents of the University of California.
+/*
+ * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -24,9 +24,9 @@
 // interest.hpp includes common.hpp; common.hpp shouldn't be used from external program
 #include "interest.hpp"
 
-// validator-config.hpp indirectly includes <boost/property_tree/ptree.hpp>
+// util/config-file.hpp indirectly includes <boost/property_tree/ptree.hpp>
 // which in turn imports Boost placeholders
-#include "security/validator-config.hpp"
+#include "util/config-file.hpp"
 
 // It's intentional to write "using namespace",
 // to simulate an external program linked against ndn-cxx.