fix variable names to interact with autovpn

autoca/ca_app.py

@@ -27,7 +27,7 @@ def content_type(ctype):
 def auth(fn):
     @functools.wraps(fn)
     def _auth_wrapper(*args, **kwargs):
-        secret = current_app.config.get('SHARED_SECRET')
+        secret = current_app.config.get('CA_SHARED_SECRET')
         if secret and request.headers.get('X-Shared-Secret') != secret:
             return make_response('Unauthorized', 401)
         return fn(*args, **kwargs)
@@ -95,7 +95,7 @@ def sign():
 def make_app(ca_instance):
     app = Flask(__name__)
     app.register_blueprint(ca_app)
-    app.config.from_envvar('CA_SETTINGS', silent=True)
+    app.config.from_envvar('CA_APP_SETTINGS', silent=True)
     app.ca = ca_instance
     return app