Make the index.html files the visible overview menu entry

And move menu entry definition into a page that the user has no reason to navigate to

Signed-off-by: Sven Dowideit <SvenDowideit@home.org.au>

docs/menu.md

@@ -0,0 +1,23 @@
+<!--[metadata]>
++++
+title = "Docker Registry"
+description = "High-level overview of the Registry"
+keywords = ["registry, on-prem, images, tags, repository, distribution"]
+type = "menu"
+[menu.main]
+identifier="smn_registry"
+parent="mn_components"
++++
+<![end-metadata]-->
+
+# Overview of Docker Registry Documentation
+
+The Docker Registry documentation includes the following topics:
+
+* [Docker Registry Introduction](index.md)
+* [Understanding the Registry](introduction.md)
+* [Deploying a registry server](deploying.md)
+* [Registry Configuration Reference](configuration.md)
+* [Notifications](notifications.md)
+* [Recipes](recipes/index.md)
+* [Getting help](help.md)