[css-rhythm-1][editorial] Updated Changes section

Author: SebastianZ

css-rhythm-1/Overview.bs

@@ -605,6 +605,9 @@ Changes {#changes}
 
 	Changes since the <a href="https://www.w3.org/TR/2017/WD-css-rhythm-1-20170302/">First Public Working Draft</a> include:
 
+	* Added interaction with East Asian casual vertical rhythms to introduction.
+	* Defined handling of truncated margins.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/1260">Issue 1260</a>)
 	* Added ''block-step-insert/margin-box'' to 'block-step-insert'
 		and renamed other values to match the ''*-box'' pattern.
 		(<a href="https://github.com/w3c/csswg-drafts/issues/10486">Issue 10486</a>)