Use the same serializer for all contact related actions

Also, rerun the response with an RFC4627 formatter

lib/serializers/registrant_api/contact.rb

@@ -0,0 +1,36 @@
+module Serializers
+  module RegistrantApi
+    class Contact
+      attr_reader :contact
+
+      def initialize(contact)
+        @contact = contact
+      end
+
+      def to_json
+        {
+          id: contact.uuid,
+          name: contact.name,
+          code: contact.code,
+          ident: {
+            code: contact.ident,
+            type: contact.ident_type,
+            country_code: contact.ident_country_code,
+          },
+          email: contact.email,
+          phone: contact.phone,
+          fax: contact.fax,
+          address: {
+            street: contact.street,
+            zip: contact.zip,
+            city: contact.city,
+            state: contact.state,
+            country_code: contact.country_code,
+          },
+          auth_info: contact.auth_info,
+          statuses: contact.statuses
+        }
+      end
+    end
+  end
+end