This method will send SSH_FXP_EXTENDED packet to remote server.
It is assumed that Data argument contains preformatted data
that follows rules of SSH protocol, and that follows rules of
extended command that is being sent. If you provide Data with
String or numeric value, then wodSFTP sends it with leading 4 bytes
as their size, and then actual data. If you provide Data as
byte array, then byte array is sent 'as is' without interference of
wodSFTP.
ExtendedCmdReply event will be fired if command was successful and
has some data to return back.
Done event will be
fired if there was an error, or only simple OK was returned by
remote side. Only of of those events will be fired, never both.
You should also check
Extensions property
to determine what extensions are supported by the server, since most
of them will announce supported extensions during connection time..
ExtendedCmd Method
