Store artifacts from the remote Jenkins slave if present

- collect artifacts from the remote Jenkins slave
  if $jenkins_slave_node_name != ${NODE_NAME}

- store py.test logs into files with different names to
  avoid overwrites

Change-Id: I1ba4fe425c5400f9095e5cd8b7e3d901be01d288
diff --git a/tcp_tests/logger.py b/tcp_tests/logger.py
index 2c73364..1d1c1f1 100644
--- a/tcp_tests/logger.py
+++ b/tcp_tests/logger.py
@@ -24,7 +24,8 @@
 logging.basicConfig(level=logging.DEBUG,
                     format='%(asctime)s - %(levelname)s %(filename)s:'
                     '%(lineno)d -- %(message)s',
-                    filename=os.path.join(settings.LOGS_DIR, 'tests.log'),
+                    filename=os.path.join(settings.LOGS_DIR,
+                                          settings.LOG_NAME),
                     filemode='w')
 
 console = logging.StreamHandler()