build: various updates

 * Upgrade waf to 2.0.14
 * Sync default compiler flags with ndn-cxx
 * Simplify compilation of unit-tests

Change-Id: I36508fc7d679a951342a3abfeb0c8cb18dbfda51
diff --git a/tests/wscript b/tests/wscript
index a32e9d8..4ba1620 100644
--- a/tests/wscript
+++ b/tests/wscript
@@ -1,21 +1,15 @@
 # -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-
-from waflib import Utils
 
 top = '..'
 
 def build(bld):
-    bld.objects(
-        target='tests-main',
-        source='main.cpp',
-        use='libndn-nac')
-
     config_path = 'TMP_TESTS_PATH="%s"' % bld.bldnode.make_node('tmp-files')
 
     bld.program(
         target='../unit-tests',
         name='unit-tests',
-        source=bld.path.ant_glob('**/*.cpp', excl='main.cpp'),
-        use='libndn-nac tests-main',
-        includes=['.'],
+        source=bld.path.ant_glob('**/*.cpp'),
+        use='libndn-nac',
+        includes='.',
         install_path=None,
         defines=[config_path])