Configuration written to settings.php during install

[grasmash]

Due to some very odd behavior in Drupal core, we must use require rather than require_once when including files in settings.php.

If we do not, the imported variable values from the required files will not be available at all stages of the Drupal installation process. This causes $config_directories['sync'] to be empty at an inopportune time, which causes Drupal to write various configuration settings directly to settings.php via drupal_rewrite_settings().