/**
  * Register hooks and load options.
  *
  * @since 1.0.0
  *
  * @uses Registry::load() to load the options.
  * @uses Loader::register_hooks() to setup plugin management.
  * @uses System::register_hooks() to setup global functionality.
  * @uses Backend::register_hooks() to setup backend functionality.
  * @uses AJAX::register_hooks() to setup AJAX functionality.
  * @uses Manager::register_hooks() to setup admin screens.
  * @uses Documenter::register_hooks() to setup admin documentation.
  */
 public static function setup()
 {
     // Setup the registry
     Registry::load();
     // Register the Installer stuff
     Installer::register_hooks();
     // Register global hooks
     self::register_hooks();
     // Register the hooks of the subsystems
     Backend::register_hooks();
     AJAX::register_hooks();
     Manager::register_hooks();
     Documenter::register_hooks();
 }