[css-cascade] Update Changes list

Author: fantasai

css-cascade/Overview.bs

@@ -945,6 +945,7 @@ Changes</h2>
 
 	<ul>
 		<li>Renamed <css>default</css> keyword to ''revert''.
+		<li>Allowed dropping duplicate parentheses in ''supports()'' syntax when it only contains one declaration.
 	</ul>
 
 <h3 id="additions-l3">

css-cascade/issues.txt

@@ -1,5 +1,5 @@
-Draft:    http://www.w3.org/TR/2013/CR-css-cascade-3-20131003/
-Title:    CSS Cascading and Inheritance Level 3
+Draft:    http://www.w3.org/TR/2015/WD-css-cascade-4-20150421/
+Title:    CSS Cascading and Inheritance Level 4
 
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 Issue 1.