Add ability to delete all tags (#2200)

* Add ability to delete all tags

* Downcase resource for confirmation

* Clean up deletion resource names

* titleize button

config/routes.rb

@@ -64,6 +64,7 @@ Rails.application.routes.draw do
 
   resources :tags, except: :show do
     resources :deletions, only: %i[new create], module: :tag
+    delete :destroy_all, on: :collection
   end
 
   namespace :category do