Adds CC-by-SA as well as the copyright.

index.html

@@ -283,6 +283,10 @@
             <div class="info__copy">
 
               <p>EdX welcomes and appreciates your comments on and requests for documentation. Just email us at <a href="mailto:docs@edx.org">docs@edx.org</a>.</p>
+              <br />
+              <br />
+        <p><a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by-sa/4.0/80x15.png" /></a><br>
+        These works by <a xmlns:cc="http://creativecommons.org/ns#" href="http://open.edx.org" property="cc:attributionName" rel="cc:attributionURL">edX Inc.</a> are licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/">Creative Commons Attribution-ShareAlike 4.0 International License</a>.</p>
             </div>
           </div>
         </aside>