TODO
====
- add support for capture_stderr option in constructor
- port to OpenVMS
- add support for later protocol versions
- add support for encodings
- improve password login, remove Expect dependency and try to backport
as much as possible fron Net::OpenSSH
- detect unknown host key checking
DONE
====
- add support for new extension methods available from late OpenSSH
SFTP server (http://www.sfr-fresh.com/unix/misc/openssh-5.1.tar.gz:a/ssh/PROTOCOL)
- add support for unix2dos and dos2unix transformations on the fly for get and put.
- add support con restarting transfer to put, get and derived methods.