PHP-FPM handling fixes

This commit fixes the way how froxlor handles PHP-FPM vhosts. It correts the user/group combination for PHP-FPM/SuExec and distingues between SSL en-/disabled Froxlor vhosts, such that php-fpm starts without a complain. Froxlor is able to create it's own vhost with php-fpm since this patch. OS is gentoo.