Add explit admin actions to (re)subscribe/unsubscribe remote accounts (#3640)

* Add explit admin actions to (re)subscribe/unsubscribe remote accounts
and re-download avatar/header

* Improve how admin NSFW toggle looks

config/routes.rb

@@ -85,6 +85,12 @@ Rails.application.routes.draw do
     end
 
     resources :accounts, only: [:index, :show] do
+      member do
+        post :subscribe
+        post :unsubscribe
+        post :redownload
+      end
+
       resource :reset, only: [:create]
       resource :silence, only: [:create, :destroy]
       resource :suspension, only: [:create, :destroy]