Disable forbidden ip feature for local shadowsocks

Since forbidden ip is server-side only, disable it for local-side.
This commit also supress warning about IPv6 loopback because I can
confirm ::1/128 is the only loopback address, not like IPv4.

shadowsocks/utils.py

@@ -186,7 +186,6 @@ def get_config(is_local):
     config['verbose'] = config.get('verbose', False)
     config['local_address'] = config.get('local_address', '127.0.0.1')
     config['local_port'] = config.get('local_port', 1080)
-    config['forbidden_ip'] = IPNetwork(config.get('forbidden_ip', '127.0.0.0/8,::1'))
     if is_local:
         if config.get('server', None) is None:
             logging.error('server addr not specified')
@@ -194,6 +193,8 @@ def get_config(is_local):
             sys.exit(2)
     else:
         config['server'] = config.get('server', '0.0.0.0')
+        config['forbidden_ip'] = \
+            IPNetwork(config.get('forbidden_ip', '127.0.0.0/8,::1/128'))
     config['server_port'] = config.get('server_port', 8388)
 
     if is_local and not config.get('password', None):