Loading from same-origin source - more secure, and works on Firefox

_includes/javascript.html

@@ -1,3 +1,3 @@
 <!-- Javascript placed at the end of the document so the pages load faster -->
-<script src="http://software-carpentry.org/v5/js/jquery-1.9.1.min.js"></script>
+<script src="js/jquery.min.js"></script>
 <script src="css/bootstrap/bootstrap-js/bootstrap.js"></script>