Edited copyright.html with Atlas code editor

Author: kristenORM

copyright.html

@@ -34,6 +34,7 @@ <h1 class="revisions">Revision History for the Second Edition</h1>
 <ul class="releases">
 	<li><span class="revdate">2017-06-01:</span> First Release</li>
 	<li><span class="revdate">2017-07-21:</span> Second Release</li>
+	<li><span class="revdate">2018-03-23:</span> Third Release</li>
 </ul>
 </div>