Some servers require the user to be logged in to run FEAT
ftp://serverftp:2121: Connecting to FTP server
FTP Rx: "220 DrFTPD+ 2.0 (+STABLE+) $Revision: 1949 $ http://drftpd.org"
FTP Tx: "AUTH TLS"
FTP Rx: "234 AUTH TLS successful"
FTP Tx: "FEAT"
FTP Rx: "530 Not logged in."
pure-ftpd 1.0.49-4 as supplied as part of Ubuntu 20.04 advertises UTF8
support in the FEAT command but the OPTS command fails to turn it on.
OPTS UTF8 ON
504 Unknown command
This patch introduces a workaround to ignore the error which enables
this library to work with this version of pure-ftpd. Filezilla appears
to ignore this error in a similar way.