added a note about the fact that some transports need proc_* PHP functions to work properly
added a note about the fact that some transports need proc_* PHP functions to work properly

Dubz/swiftmailer,zghosts/swiftmailer,c960657/swiftmailer,zghosts/swiftmailer,Chhunlong/swiftmailer,gburyakovsky/swiftmailer,c960657/swiftmailer,papagel/swiftmailer,handautsav/swiftmailer,denpamusic/swiftmailer,voku/swiftmailer,gencer/swiftmailer,denpamusic/swiftmailer,peterkokot/swiftmailer,handautsav/swiftmailer,UofSC/php-shared-functions,papagel/swiftmailer,deguif/swiftmailer,Pardot/swiftmailer,voku/swiftmailer,Pardot/swiftmailer,swiftmailer/swiftmailer,kuslahne/swiftmailer,fvosberg/swiftmailer,Rotzbua/swiftmailer,fvosberg/swiftmailer,michabbb-backup/swiftmailer,peterkokot/swiftmailer,peterkokot/swiftmailer,jamesggordon/swiftmailer,robertklein/swiftmailer,gburyakovsky/swiftmailer,swiftmailer/swiftmailer,Pardot/swiftmailer,tweakers-dev/swiftmailer,kuslahne/swiftmailer,Dubz/swiftmailer,gencer/swiftmailer,tweakers-dev/swiftmailer,michabbb-backup/swiftmailer,jamesggordon/swiftmailer,robertklein/swiftmailer,deguif/swiftmailer,Rotzbua/swiftmailer,Pardot/swiftmailer,UofSC/php-shared-functions,UofSC/php-shared-functions,Chhunlong/swiftmailer