Split the HTML index.
diff --git a/Doc/conf.py b/Doc/conf.py
index da70669..41a6b61 100644
--- a/Doc/conf.py
+++ b/Doc/conf.py
@@ -94,6 +94,9 @@
 # Output file base name for HTML help builder.
 htmlhelp_basename = 'python' + release.replace('.', '')
 
+# Split the index
+html_split_index = True
+
 
 # Options for LaTeX output
 # ------------------------