Refactor Overview and quickstarts

Author: sdwheeler

articles/cloud-shell/.openpublishing.redirection.cloud-shell.json

@@ -1,8 +1,13 @@
 {
     "redirections": [
+        {
+            "source_path_from_root": "/articles/cloud-shell/quickstart-powershell.md",
+            "redirect_url": "/azure/cloud-shell/quickstart",
+            "redirect_document_id": true
+        },
         {
             "source_path_from_root": "/articles/cloud-shell/cloud-shell-windows-users.md",
-            "redirect_url": "/azure/cloud-shell/quickstart-powershell",
+            "redirect_url": "/azure/cloud-shell/quickstart",
             "redirect_document_id": false
         },
         {

articles/cloud-shell/TOC.yml

@@ -2,11 +2,7 @@ items:
   - name: Overview
     href: overview.md
   - name: Quickstart
-    items:
-      - name: Bash - Quickstart
-        href: quickstart.md
-      - name: PowerShell - Quickstart
-        href: quickstart-powershell.md
+    href: quickstart.md
   - name: Features & tools
     href: features.md
   - name: Tutorials