update front page of devstack docs

The devstack docs have gotten a bit meandering so even the quick start
guide doesn't get you to a working setup without referencing other
pages. This attempts to pull this back in a bit.

Change-Id: I608331cbdae9cbe4f3e8bd3814415af0390a54d0
diff --git a/doc/source/site-map.rst b/doc/source/site-map.rst
new file mode 100644
index 0000000..480d6aa
--- /dev/null
+++ b/doc/source/site-map.rst
@@ -0,0 +1,21 @@
+:orphan:
+
+.. the TOC on the front page actually makes the document a lot more
+   confusing. This lets us bury a toc which we can link in when
+   appropriate.
+
+==========
+ Site Map
+==========
+
+.. toctree::
+   :glob:
+   :maxdepth: 3
+
+   overview
+   configuration
+   plugins
+   plugin-registry
+   faq
+   hacking
+   guides