Add feature flags, RS dashboard dummy

closes #124
refs #94

config/routes.rb

@@ -19,6 +19,8 @@ Rails.application.routes.draw do
   resources :invitations, only: ['index', 'show', 'create', 'destroy']
 
   namespace :services do
+    get 'storage', to: 'remotestorage#dashboard'
+
     resources :lightning, only: [:index] do
       collection do
         get 'transactions'
@@ -62,6 +64,7 @@ Rails.application.routes.draw do
 
   authenticate :user, ->(user) { user.is_admin? } do
     mount Sidekiq::Web => '/sidekiq'
+    mount Flipper::UI.app(Flipper) => '/flipper'
   end
 
   # Letter Opener (open "sent" emails in dev and staging)