Changed log name in tester email.

tester.py

@@ -185,7 +185,7 @@ Content-transfer-encoding: utf-8
                 recipients=recipients,
                 status='OK' if exit_code == 0 else 'KO',
                 date=now.strftime('%Y-%m-%d %H:%M:%S'),
-                log_name='results_' + now.strftime('%Y-%m-%d_%H-%M-%S') + '.txt',
+                log_name='results_%s_%s.txt' % (hostname, now.strftime('%Y-%m-%d_%H-%M-%S')),
                 report=html_report,
                 log_content=log_content,
             )