Add Pt_BR - Fixes #788

pt_BR translation ongoing,

Author: vcaldas

docs/_templates/sidebarlogo.html

@@ -46,4 +46,5 @@ <h3>Translations</h3>
   <li><a href="https://pythonguidecn.readthedocs.io/zh/latest/">Chinese</a></li>
   <li><a href="https://python-guide-ja.readthedocs.io/en/latest/">Japanese</a></li>
   <li><a href="https://python-guide-kr.readthedocs.io/ko/latest/">Korean</a></li>
+  <li><a href="http://python-guide-pt-br.readthedocs.io/pt_BR/latest/">Brazilian Portuguese</a></li>
 </ul>