ftp ASCII transfers in general need fixing

 * Make CURLOPT_FTPPORT support an additional port number on the IP/if/name,

   like "blabla:[port]" or possibly even "blabla:[portfirst]-[portsecond]".

 * FTP ASCII upload does not follow RFC959 section 3.1.1.1: "The sender

   converts the data from an internal character representation to the standard

   8-bit NVT-ASCII representation (see the Telnet specification).  The

   receiver will convert the data from the standard form to his own internal

   form."

 * FTP ASCII transfers do not follow RFC959. They don't convert the data

   accordingly.

 * Since USERPWD always override the user and password specified in URLs, we

   might need another way to specify user+password for anonymous ftp logins.