#2 ChannelSFTP path handling

[Gernot Eger]

With Jsch 0.1.24 (and 0.1.21) in combination with
apache commons vfs and a Cygwin SFTP Server most
commands fail. This patch solves:
<a href="http://sourceforge.net/tracker/index.php?
func=detail&aid=1395897&group_id=64920&atid=509122">139
5897</a>

[Gernot Eger]

Patch for bug 1395897