Wait for ssh broken for jump-hosts

[howech]

When we launch instances, by default we wait for ssh to become available before saying that we are really done. We check to see that ssh is available by seeing if we can open port 22 on our target instance's public ip address.

However, when we actually try to ssh to the machine, we use fancy ssh logic built into knife - which actually respects our .ssh/config file. It could be that when we try to ssh to the target machine, we are not really going over port 22. We should change the ssh-is-ready logic to actually use the right method of finding whether or not ssh is ready.