Remove public stats

This page isn't linked from anywhere and most Consul Democracy
installations don't even know it exists, so it's useless for most
people.

If we ever bring it back, we should at least add a link pointing to this
page.

config/routes.rb

@@ -32,7 +32,6 @@ Rails.application.routes.draw do
   get "/consul.json", to: "installation#details"
   get "robots.txt", to: "robots#index"
 
-  resources :stats, only: [:index]
   resources :images, only: [:destroy]
   resources :documents, only: [:destroy]
   resources :follows, only: [:create, :destroy]