Rework docs sidebar to have some nesting.

Signed-off-by: Matt Moyer <moyerm@vmware.com>

site/content/docs/_index.md

@@ -2,6 +2,10 @@
 title: "Pinniped Documentation"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Overview
+    weight: 1
 ---
 
 ![Pinniped Logo](/docs/img/pinniped_logo.svg)

site/content/docs/architecture.md

@@ -2,6 +2,10 @@
 title: "Pinniped Architecture"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Architecture
+    weight: 100
 ---
 
 # Architecture

site/content/docs/concierge-and-supervisor-demo.md

@@ -2,6 +2,10 @@
 title: "Pinniped Concierge and Supervisor Demo"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Concierge with Supervisor
+    parent: demo
 ---
 
 # Trying Pinniped Supervisor and Concierge

site/content/docs/concierge-only-demo.md

@@ -2,6 +2,11 @@
 title: "Pinniped Concierge Only Demo"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Concierge with Webhook
+    parent: demo
+    weight: 100
 ---
 
 # Trying Pinniped Concierge

site/content/docs/demo.md

@@ -2,6 +2,11 @@
 title: "Pinniped Demo"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Demo
+    identifier: demo
+    weight: 40
 ---
 
 # Trying Pinniped

site/content/docs/install.md

@@ -2,6 +2,10 @@
 title: "Installing Pinniped"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Install
+    weight: 10
 ---
 
 # Installing Pinniped

site/content/docs/scope.md

@@ -2,6 +2,10 @@
 title: "Pinniped Scope"
 cascade:
   layout: docs
+menu:
+  docs:
+    name: Scope
+    weight: 200
 ---