[css-ui-4] Update link defaults

Author: frivoal

css-ui-4/Overview.bs

@@ -71,6 +71,8 @@ spec:css-pseudo-4; type:selector; text:::after
 spec:css-pseudo-4; type:selector; text:::first-line
 spec:css-pseudo-4; type:selector; text:::first-letter
 spec:selectors-4; type:selector; text::checked
+spec:css-display-3; type:property; text:display
+spec:css-color-4; type:value; text:currentcolor
 </pre>
 
 <pre class="anchors">