lib: Upgrade Dojo and Dijit from 1.8.3 to 1.12.1

The itemNode and expandoNode elements have changed from img to
span (https://bugs.dojotoolkit.org/ticket/16699), so we now put our
tree icons inside them rather than replacing them.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

lib/dojo/README.md

@@ -0,0 +1,31 @@
+# dojo
+
+**dojo** is the foundation package of the Dojo Toolkit. Sometimes referred to as the “core”, it contains the most
+generally applicable sub-packages and modules. The dojo package covers a wide range of functionality like AJAX, DOM
+manipulation, class-type programming, events, promises, data stores, drag-and-drop and internationalization libraries.
+
+## Installing
+
+Installation instructions are available at [dojotoolkit.org/download][download].
+
+## Getting Started
+
+If you are starting out with Dojo, the following resources are available to you:
+
+* [Tutorials][]
+* [Reference Guide][]
+* [API Documentation][]
+* [Community Forum][]
+
+## License and Copyright
+
+The Dojo Toolkit (including this package) is dual licensed under BSD 3-Clause and AFL.  For more information on the
+license please see the [License Information][].  The Dojo Toolkit is Copyright (c) 2005-2016, The JS Foundation.  All
+rights reserved.
+
+[download]: http://dojotoolkit.org/download/
+[Tutorials]: http://dojotoolkit.org/documentation/
+[Reference Guide]: http://dojotoolkit.org/reference-guide/
+[API Documentation]: http://dojotoolkit.org/api/
+[Community Forum]: http://dojotoolkit.org/community/
+[License Information]: http://dojotoolkit.org/license