fix python 3.2

.travis.yml

@@ -26,5 +26,4 @@ script:
   - python tests/test.py -c tests/salsa20.json
   - python tests/test.py -c tests/server-multi-ports.json
   - python tests/test.py -c tests/server-multi-passwd.json tests/server-multi-passwd-client-side.json
-  - python tests/test.py -c tests/server-multi-passwd-table.json
   - python tests/test.py -c tests/workers.json

shadowsocks/utils.py

@@ -207,7 +207,7 @@ def get_config(is_local):
         level = logging.INFO
     logging.basicConfig(level=level,
                         format='%(asctime)s %(levelname)-8s %(message)s',
-                        datefmt='%Y-%m-%d %H:%M:%S', filemode='a+')
+                        datefmt='%Y-%m-%d %H:%M:%S')
 
     check_config(config)