Better error handling, Efforts to run non-root with occasional sudo

ucloud/settings/__init__.py

@@ -47,8 +47,15 @@ class Settings(object):
             }
         except configparser.Error as err:
             raise configparser.Error('{} in config file {}'.format(err.message, self.config_file)) from err
-
-        return Etcd3Wrapper(*args, **kwargs)
+        else:
+            try:
+                wrapper = Etcd3Wrapper(*args, **kwargs)
+            except Exception as err:
+                logger.error('etcd connection not successfull. Please check your config file.'
+                             '\nDetails: %s\netcd connection parameters: %s', err, kwargs)
+                sys.exit(1)
+            else:
+                return wrapper
         
     def read_internal_values(self):
         self.config_parser.read_dict({