tests: introduce unit testing

As a sample, this commit also includes a test suite for
ndn::ping::client::StatisticsCollector class.

refs #2795

Change-Id: Ia0c7522ae26bee1cc9d172c7379ab62f84325ed7
diff --git a/tests/wscript b/tests/wscript
new file mode 100644
index 0000000..6066890
--- /dev/null
+++ b/tests/wscript
@@ -0,0 +1,15 @@
+# -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-
+top = '..'
+
+def build(bld):
+    if not bld.env['WITH_TESTS']:
+        return
+
+    tools = bld.path.ant_glob('*', dir=True, src=False)
+
+    bld(target='../unit-tests',
+        features='cxx cxxprogram',
+        source=bld.path.ant_glob('**/*.cpp'),
+        use=['core-objects'] + ['%s-objects' % tool for tool in tools],
+        headers='../common.hpp boost-test.hpp',
+        )