Migrate to C++17 and refactor

Change-Id: I53407266939258990a1c3a9363c3ebe9ea113fd2
diff --git a/tests/unit-tests/redirection-policy.t.cpp b/tests/unit-tests/redirection-policy.t.cpp
index d8d5203..bcc0d9f 100644
--- a/tests/unit-tests/redirection-policy.t.cpp
+++ b/tests/unit-tests/redirection-policy.t.cpp
@@ -21,10 +21,10 @@
 #include "redirection/redirection-policy.hpp"
 #include "redirection/redirection-param.hpp"
 #include "redirection/redirection-email.hpp"
+
 #include "test-common.hpp"
 
-namespace ndncert {
-namespace tests {
+namespace ndncert::tests {
 
 BOOST_AUTO_TEST_SUITE(TestRedirectionPolicy)
 
@@ -76,5 +76,4 @@
 
 BOOST_AUTO_TEST_SUITE_END() // TestNameAssignment
 
-} // namespace tests
-} // namespace ndncert
+} // namespace ndncert::tests