📝 Update Release Notes

docs/release-notes.md

@@ -1,5 +1,7 @@
 ## Next release
 
+* Document response models using unions and lists, updated at: <a href="https://fastapi.tiangolo.com/tutorial/extra-models/" target="_blank">Extra Models</a>. PR <a href="https://github.com/tiangolo/fastapi/pull/108" target="_blank">#108</a>.
+
 ## 0.10.1
 
 * Add docs and tests for <a href="https://github.com/encode/databases" target="_blank">encode/databases</a>. New docs at: <a href="https://fastapi.tiangolo.com/tutorial/async-sql-databases/" target="_blank">Async SQL (Relational) Databases</a>. PR <a href="https://github.com/tiangolo/fastapi/pull/107" target="_blank">#107</a>.