vty_test_runner.py: make unittest print all output by default

Add option to TextTestRunner that shows print output on stdout.
It's better to see everything in our jenkins runs and not hide test output.

Change-Id: If4be1ad1c81c9ed4ab9b208b4c6d1e4b2cc8fdd5
diff --git a/openbsc/tests/vty_test_runner.py b/openbsc/tests/vty_test_runner.py
index 5bb27a8..8dc4f70 100644
--- a/openbsc/tests/vty_test_runner.py
+++ b/openbsc/tests/vty_test_runner.py
@@ -1357,7 +1357,7 @@
     add_nat_test(suite, workdir)
     add_gbproxy_test(suite, workdir)
     add_sgsn_test(suite, workdir)
-    res = unittest.TextTestRunner(verbosity=verbose_level).run(suite)
+    res = unittest.TextTestRunner(verbosity=verbose_level, stream=sys.stdout).run(suite)
     sys.exit(len(res.errors) + len(res.failures))
 
 # vim: set shiftwidth=4 expandtab nocin ai