Update README

Author: tjb346

README.md

@@ -178,6 +178,12 @@ If you are carefully curating your `title` properties already to ensure no dupli
 
 If this option results in conflicts, you will need to manually override class names instead via the `class_overrides` option.
 
+### enumerate_duplicate_model_names
+
+Even with `use_path_prefixes_for_title_model_names` set to `true`, duplicate model class names can occur. By default, when duplicates are encountered they will be skipped.
+
+Setting `enumerate_duplicate_model_names` to `true` in your config file will result in a number being added to duplicate names starting with 2. For instance, if `MyModelName` already exists, then the next time a model with that name is encountered, it will be named `MyModelName2`, then `MyModelName3` and so on.
+
 ### http_timeout
 
 By default, the timeout for retrieving the schema file via HTTP is 5 seconds. In case there is an error when retrieving the schema, you might try and increase this setting to a higher value.