gtkui: let the server determine if dir is [truly] not listable
gtkui: let the server determine if dir is [truly] not listable

if the server is running as root (I know it's crazy but it happens),
it can do anything

Servers running on Windows [ftpdmin.exe] may report wrong permissions, at least through WINE

masneyb/gftp,masneyb/gftp