📝 Update release notes

docs/release-notes.md

@@ -1,5 +1,7 @@
 ## Next release
 
+* Make Travis run Ubuntu Xenial (newer version) and Python 3.7 instead of Python 3.7-dev. PR <a href="https://github.com/tiangolo/fastapi/pull/92" target="_blank">#92</a> by <a href="https://github.com/blueyed" target="_blank">@blueyed</a>.
+
 * Fix duplicated param variable creation. PR <a href="https://github.com/tiangolo/fastapi/pull/123" target="_blank">#123</a> by <a href="https://github.com/yihuang" target="_blank">@yihuang</a>.
 
 * Add docs about <a href="https://fastapi.tiangolo.com/tutorial/extending-openapi/" target="_blank">Extending OpenAPI</a>. PR <a href="https://github.com/tiangolo/fastapi/pull/126" target="_blank">#126</a>.