Fix kubectl 404

1. Update script to:
   a) Rename kubectl.md to index.md
   b) Remove "See Also" section from kubectl subcommands md files
2. Update the _date/reference.yml link to kubectl

_data/reference.yml

@@ -63,7 +63,7 @@ toc:
   - title: kubectl Commands
     section:
     - title: kubectl
-      path: /docs/user-guide/kubectl/kubectl/
+      path: /docs/user-guide/kubectl/
     - title: kubectl annotate
       path: /docs/user-guide/kubectl/kubectl_annotate/
     - title: kubectl api-versions