Add Admin Administrator route, controller and manage ability for admin users

config/routes.rb

@@ -207,6 +207,10 @@ Rails.application.routes.draw do
       get :search, on: :collection
     end
 
+    resources :administrators, only: [:index, :create, :destroy] do
+      get :search, on: :collection
+    end
+
     scope module: :poll do
       resources :polls do
         get :search_questions, on: :member