Remove articles from application (#672)

Articles used thumbnail/feature images.  Removing until there is
an alternate solution.

app/views/layouts/cms.html.erb

@@ -47,7 +47,6 @@
               <%= nav_link_to(title: "Admin", path: admin_users_path) if current_user.admin? %>
               <%= nav_link_to(title: "Blocks", path: admin_content_blocks_path) if current_user.admin? %>
               <%= nav_link_to(title: "Pages", path: admin_content_pages_path) %>
-              <%= nav_link_to(title: "Articles", path: admin_articles_path) %>
               <li class="govuk-header__navigation-item">
                 <%= link_to "See the site", "/", class: "govuk-header__link", target: :_blank %>
               </li>

config/routes.rb

@@ -22,10 +22,10 @@
   namespace :admin do
     root to: "users#index"
     resources :users
-    resources :articles do
-      post "publish", on: :member
-      post "unpublish", on: :member
-    end
+    # resources :articles do
+    #  post "publish", on: :member
+    #  post "unpublish", on: :member
+    # end
     resources :content_pages, path: "pages" do
       get "versions", on: :member
       get "preview_of_live", on: :member
@@ -43,7 +43,7 @@
     get "/#{static_page}", to: "static_pages##{static_page.underscore}"
   end
 
-  resources :articles, only: %i[index show]
+  # resources :articles, only: %i[index show]
   resources :feedbacks, only: %i[create]
 
   get "/:section/:slug", to: "content#show"