config refactor (#1854)

* split out config

* add tests for base and app config, refactor client config out of app config

* refactor default config retrieval

* create config test class and helper functions

* move default_config into server to fix import issue

server/__init__.py

@@ -1,6 +1,5 @@
 import logging
 import sys
-
 from server.common.utils.utils import import_plugins
 
 __version__ = "0.16.0"