Nginx: Make sure that $extended_nginx_config is used as a fallback if $basic_nginx_config is not set.
Nginx: Remove not used $ip_address variable from the non-ssl vhost template.
Nginx: Fix $basic_nginx_config switch logic.
Issue #1975188 by anarcat - nginx default server overrides configured vhosts.
Nginx: Add missing stuff in the provision.api.php