Use properties in config for pass-through compat vars

Strings are immutable, so when one variable changes the other will not,
as such there is variance on config load between variables that should
be the the value of another variable.

To solve that I've moved the config into a class and made those values
read-only properties to the loaded values.

Closes: #137 #138

realms/modules/auth/oauth/models.py

@@ -5,6 +5,8 @@ from flask_oauthlib.client import OAuth
 from realms import config
 from ..models import BaseUser
 
+config = config.conf
+
 oauth = OAuth()
 
 users = {}