Add auth around admin

[Delivers #16802507]

config/initializers/rails_admin.rb

@@ -0,0 +1,5 @@
+RailsAdmin.config do |config|
+  config.authenticate_with do
+    redirect_to '/' unless signed_in? && current_user.admin?
+  end
+end

db/migrate/00000000000001_devise_create_users.rb

@@ -7,6 +7,7 @@ class DeviseCreateUsers < ActiveRecord::Migration
       t.string :email, :null => false
       t.string :voice_number
       t.string :sms_number
+      t.boolean :admin, :default => false
       t.database_authenticatable :null => false
       t.recoverable
       t.rememberable

db/schema.rb

@@ -55,12 +55,13 @@ ActiveRecord::Schema.define(:version => 4) do
   create_table "users", :force => true do |t|
     t.datetime "created_at"
     t.datetime "updated_at"
-    t.string   "name",                                                :null => false
+    t.string   "name",                                                   :null => false
     t.string   "organization"
-    t.string   "email",                               :default => "", :null => false
+    t.string   "email",                               :default => "",    :null => false
     t.string   "voice_number"
     t.string   "sms_number"
-    t.string   "encrypted_password",   :limit => 128, :default => "", :null => false
+    t.boolean  "admin",                               :default => false
+    t.string   "encrypted_password",   :limit => 128, :default => "",    :null => false
     t.string   "reset_password_token"
     t.string   "remember_token"
     t.datetime "remember_created_at"