tests: respect naming conventions and improve nesting of some test suites

Change-Id: I255c27b552b32570871a9d5f8bda814ba8723c80
Refs: #2497
diff --git a/tests/unit-tests/security/signing-helpers.t.cpp b/tests/unit-tests/security/signing-helpers.t.cpp
index 6665704..b29954c 100644
--- a/tests/unit-tests/security/signing-helpers.t.cpp
+++ b/tests/unit-tests/security/signing-helpers.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) 2013-2016 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -27,7 +27,8 @@
 namespace security {
 namespace tests {
 
-BOOST_AUTO_TEST_SUITE(SecuritySigningHelpers)
+BOOST_AUTO_TEST_SUITE(Security)
+BOOST_AUTO_TEST_SUITE(TestSigningHelpers)
 
 BOOST_AUTO_TEST_CASE(Identity)
 {
@@ -60,8 +61,9 @@
   BOOST_CHECK_EQUAL(info.getSignerName(), SigningInfo::EMPTY_NAME);
 }
 
-BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE_END() // TestSigningHelpers
+BOOST_AUTO_TEST_SUITE_END() // Security
 
 } // namespace tests
 } // namespace security
-} // namespace ndn
\ No newline at end of file
+} // namespace ndn