Edited 'config/migration.php' config file and set 'migration_enabled=TRUE' and version. Created new folder 'application/migrations'. Created new file 'application/migration/001_create_user.php' and modified fields to create a users table. Created new folder 'controllers/admin' and added file 'migration.php' to be able to run the created migration file in 'application/migration/001_create_user.php'.
Rename '001_create_user.php' to '001_create_users.php'. Created new file 'application/migrations/002_create_pages.php' and modified fields for the 'pages' table.