Add system example tests

examples/system/perfmon/example_test.py

@@ -0,0 +1,19 @@
+from __future__ import unicode_literals
+import ttfw_idf
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_WIFI')
+def test_examples_perfmon(env, extra_data):
+
+    dut = env.get_dut('perfmon', 'examples/system/perfmon')
+    dut.start_app()
+
+    dut.expect_all('example: Start',
+                   'example: Start test with printing all available statistic',
+                   'example: Start test with user defined statistic',
+                   'example: The End',
+                   timeout=60)
+
+
+if __name__ == '__main__':
+    test_examples_perfmon()