[css-align-3] Update Changes list.

Author: fantasai

css-align-3/Overview.bs

@@ -9,6 +9,7 @@ ED: https://drafts.csswg.org/css-align/
 TR: https://www.w3.org/TR/css-align-3/
 Editor: Elika J. Etemad / fantasai, Invited Expert, http://fantasai.inkedblade.net/contact, w3cid 35400
 Editor: Tab Atkins Jr., Google, http://xanthir.com/contact/, w3cid 42199
+Previous Version: https://www.w3.org/TR/2018/WD-css-align-3-20180830/
 Previous Version: https://www.w3.org/TR/2018/WD-css-align-3-20180423/
 Previous Version: https://www.w3.org/TR/2017/WD-css-align-3-20170906/
 Previous Version: https://www.w3.org/TR/2017/WD-css-align-3-20170720/
@@ -2321,6 +2322,8 @@ Appendix A: Static Position Terminology</h2>
 <h2 id="changes">
 Changes</h2>
 
+	Changes since the <a href="https://www.w3.org/TR/2018/WD-css-align-3-20180830/">30 August 2018 Working Draft</a> consist of some minor clarifications.
+
 	Changes since the <a href="https://www.w3.org/TR/2018/WD-css-align-3-20180423/">23 April 2018 Working Draft</a> include:
 	<ul>
 		<li>Better definition of how the alignment properties interact with absolutely-positioned boxes with ''left/auto'' offsets.