manually handle #1703 for note on horizontal forms

docs/upgrading.html

@@ -158,6 +158,7 @@
     <li>Default form style is now vertical (stacked) to use less CSS and add greater flexibility</li>
     <li>Form classes standardized with <code>.form-</code> required as a prefix</li>
     <li>New built-in form defaults for search, inline, and horizontal forms</li>
+    <li>For horizontal forms, previous classes <code>.clearfix</code> and <code>.input</code> are equivalent to the new <code>.control-group</code> and <code>.controls</code>.</li>
     <li>More flexible horizontal form markup with classes for all styling, including new optional class for the <code>label</code></li>
     <li>Form states: colors updated and customizable via new LESS variables</li>
   </ul>