Add section numbering to some of the larger subdocuments.
diff --git a/Doc/documenting/index.rst b/Doc/documenting/index.rst
index 5ec9fb6..b64dc75 100644
--- a/Doc/documenting/index.rst
+++ b/Doc/documenting/index.rst
@@ -23,6 +23,7 @@
 are more than welcome as well.
 
 .. toctree::
+   :numbered:
 
    intro.rst
    style.rst