Integrate auction

Closes #874

app/controllers/api/v1/base_controller.rb

@@ -0,0 +1,18 @@
+require 'rails5_api_controller_backport'
+
+module Api
+  module V1
+    class BaseController < ActionController::API
+      private
+
+      def authenticate
+        ip_allowed = allowed_ips.include?(request.remote_ip)
+        head :unauthorized unless ip_allowed
+      end
+
+      def allowed_ips
+        ENV['auction_api_allowed_ips'].split(',').map(&:strip)
+      end
+    end
+  end
+end