Allow forcing HTTPS in URL generation (#92)

* Force HTTPS feature
* Add docs

custom_components/auth_oidc/__init__.py

@@ -23,6 +23,8 @@ from .config import (
     ROLES,
     NETWORK,
     FEATURES_INCLUDE_GROUPS_SCOPE,
+    FEATURES_DISABLE_FRONTEND_INJECTION,
+    FEATURES_FORCE_HTTPS,
 )
 
 # pylint: enable=useless-import-alias