[css-exclusions] add changelog entry

Author: astearns

css-exclusions/Exclusions.src.html

@@ -2121,6 +2121,7 @@ <h2 class="no-num" id="change-log">Change Log</h2>
 
       <h3>Since <a href="http://www.w3.org/TR/2012/WD-css3-exclusions-20120503/">May 3rd 2012</a></h3>
       <ul>
+          <li>Changed shape-inside to contribute to the wrapping context</li>
           <li>Defined exclusion edges relative to wrapping content's writing mode</li>
           <li>Made use of start, end, before and after consistent</li>
           <li>Added interpolation for basic shapes</li>

css-exclusions/Overview.html

@@ -2996,6 +2996,8 @@ <h3 id=since-may-3rd-2012><span class=secno>5.7. </span>Since <a
    2012</a></h3>
 
   <ul>
+   <li>Changed shape-inside to contribute to the wrapping context
+
    <li>Defined exclusion edges relative to wrapping content's writing mode
 
    <li>Made use of start, end, before and after consistent