feat: fix issues in invite user.

feat: fix update last login at after login.

server/src/system/migrations/20190822214242_create_users_table.js

@@ -13,6 +13,7 @@ exports.up = function (knex) {
     
     table.integer('tenant_id').unsigned();
 
+    table.date('invite_accepted_at');
     table.date('last_login_at');
     table.timestamps();
   }).then(() => {

server/src/system/models/index.js

@@ -6,6 +6,7 @@ import Voucher from './Subscriptions/Voucher';
 import Tenant from './Tenant';
 import SystemUser from './SystemUser';
 import PasswordReset from './PasswordReset';
+import Invite from './Invite';
 
 export {
   Plan,
@@ -15,4 +16,5 @@ export {
   Tenant,
   SystemUser,
   PasswordReset,
+  Invite,
 }