Remove MathJax rather than trying to relocate it, for now

sanitise.py

@@ -9,8 +9,13 @@
 html = html.replace("https://cdnjs.cloudflare.com/ajax/libs/jquery/2.0.3/jquery.min.js",
                     "js/require-2.0.3.min.js")
 
-html = html.replace("https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_HTML",
-                    "js/MathJax.js")
+# MathJax is not a single script that's easy to relocate. Eventually we may want to follow
+# http://docs.mathjax.org/en/latest/start.html#installing-your-own-copy-of-mathjax
+# but for now, we don't actually use MathJax so let's remove it.
+#html = html.replace("https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_HTML",
+#                    "js/MathJax.js")
+
+html = html.replace('<script src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_HTML"></script>', '')
 
 assert 'script src="http' not in html, "HTMLified Notebook appears to contain unhandled 3rd party JS, please fix sanitise.py"
 assert 'src="http' not in html, "HTMLified Notebook appears to contain unhandled 3rd party embed, please fix sanitise.py"