Add warning

docs/configuration.md

@@ -6,6 +6,9 @@ Default: `[]` (empty list)
 
 A list of models provided by other plugins which should be exempt from branching support. (Only models which support change logging need be listed; all other models are ineligible for branching support.)
 
+!!! warning
+    A model may not be exempted from branching support if it has one or more relationships to models for which branching is supported. Branching **must** be supported consistently for all inter-related models; otherwise, data corruption can occur. Configure this setting only if you have a specific need to disable branching for certain models provided by plugins.
+
 Models must be specified by app label and model name, as such:
 
 ```python