ftp library cleanup and fixes according to PR comments
ftp library cleanup and fixes according to PR comments

iolevel/peachpie,iolevel/peachpie-concept,peachpiecompiler/peachpie,iolevel/peachpie-concept,iolevel/peachpie-concept,peachpiecompiler/peachpie,iolevel/peachpie,peachpiecompiler/peachpie,iolevel/peachpie