/**
  * Constructor, load parent constructor and set up cachable variables.
  */
 protected function __construct()
 {
     parent::__construct();
     $this->settings_field = THE_SEO_FRAMEWORK_SITE_OPTIONS;
     $this->o_plugin_updated = 'updated_' . THE_SEO_FRAMEWORK_DB_VERSION;
     $this->seo_settings_page_slug = 'theseoframework-settings';
     //* Set up site settings and save/reset them
     add_action('admin_init', array($this, 'register_settings'), 5);
     //* Update site options at plugin update.
     add_action('admin_init', array($this, 'site_updated_plugin_option'), 30);
 }