Mention the dependencies

Author: paulproteus

README.rst

@@ -5,4 +5,8 @@ To contribute, file issues on Github or email me <[email protected]>.
 Text in this document may be shared under the terms of
 Creative Commons Zero <http://creativecommons.org/publicdomain/zero/1.0/>.
 
+Note that this Sphinx document requires that you have
+"sphinx-bootstrap-theme" installed from PyPI, as well
+as sphinx itself.
+
 -- Asheesh.