Fix reading FTP data is ASCII mode In ASCII mode, if you don't have a line in the next block that you're trying to read, then ftplib would set the first character to '\0'.
Upstream probably intented to return an empty string when requesting to read only 1 character since that doesn't make much sense when the EOL delimiter is 2 characters already (\r\n). However, due to the way data is read, max can be set to 1 just after having read max-1 legitimate bytes and we should not be overwriting the first byte.
