Changed fpm-config var description...

* start_servers not used if ondemand, same with min and max_spare_servers
[http://www.php.net/manual/de/install.fpm.configuration.php#pm]
Removed unecessary 'start_servers' if pm = ondemand

http://www.php.net/manual/de/install.fpm.configuration.php#pm.start-servers
Changed fpm-config var description...

* start_servers not used if ondemand, same with min and max_spare_servers
[http://www.php.net/manual/de/install.fpm.configuration.php#pm]
Whoops...
Merge pull request #194 from Commifreak/master

Some FPM improvements