PHP-FPM logger refactoring

I have started refactoring of zlog (internal FPM logger) to allow better handling of user output as it is also used for catching stdout and stderr from workers.

PHP-FPM

I have been interested in PHP-FPM for some time and currently looking to various issues in it. It is basically a PHP FastCGI application that is consisting of a master process that is managing workers that execute PHP scripts.