Return nice message when etcd section is missing

ucloud/configure/main.py

@@ -1,5 +1,3 @@
-import argparse
-import sys
 import os
 
 from ucloud.settings import settings

ucloud/settings/__init__.py

@@ -30,7 +30,10 @@ class Settings(object):
         self.config_key = config_key
 
         self.read_internal_values()
+        try:
             self.config_parser.read(self.config_file)
+        except Exception as err:
+            logger.error('%s', err)
 
     def get_etcd_client(self):
         args = tuple()