[css-display-3] Add previous version links

Author: fantasai

css-display-3/Overview.bs

@@ -7,6 +7,8 @@ Shortname: css-display
 Group: csswg
 Level: 3
 TR: https://www.w3.org/TR/css-display-3/
+Previous Version: https://www.w3.org/TR/2019/CR-css-display-3-20190711/
+Previous Version: https://www.w3.org/TR/2018/CR-css-display-3-20180828/
 Previous Version: https://www.w3.org/TR/2018/WD-css-display-3-20180809/
 Previous Version: https://www.w3.org/TR/2018/WD-css-display-3-20180420/
 Previous Version: https://www.w3.org/TR/2017/WD-css-display-3-20170720/