change nav to use index files for each section; stub out index views for everything

docs/_data/nav.yml

@@ -160,7 +160,6 @@
 
 - title: Examples
   pages:
-    - title: Overview
     - title: Starter template
     - title: Grid
     - title: Jumbotron

docs/_includes/nav-docs.html

@@ -23,7 +23,7 @@
       {% endif %}
 
       <div class="bd-toc-item {{ active }}">
-        <a class="bd-toc-link" href="{{ site.baseurl }}/{{ group.title | downcase | replace: ' ', '-' }}/{{ link.title | downcase | replace: ' ', '-' || page.title | downcase | replace: ' ', '-'  }}">
+        <a class="bd-toc-link" href="{{ site.baseurl }}/{{ group.title | downcase | replace: ' ', '-' }}/">
           {{ group.title }}
         </a>
 

docs/about/index.md

@@ -0,0 +1,6 @@
+---
+layout: page
+title: About
+---
+
+todo: this entire page

docs/components/index.md

@@ -0,0 +1,6 @@
+---
+layout: page
+title: Components
+---
+
+todo: this entire page

docs/extend/index.md

@@ -0,0 +1,6 @@
+---
+layout: page
+title: Extend
+---
+
+todo: this entire page

docs/getting-started/index.md

@@ -0,0 +1,6 @@
+---
+layout: page
+title: Getting started
+---
+
+todo: this entire page

docs/layout/index.md

@@ -0,0 +1,6 @@
+---
+layout: page
+title: Layout
+---
+
+todo: this entire page