Update vendoring to allow ssh package use outside of fleet

[jasonmoo]

github.com/coreos/fleet/ssh has a nice known hosts check that is compatible with golang.org/x/crypto/ssh, but vendoring with Godeps creates a namespacing problem which prevents it from being used outside the fleet library fwict.

func EnsureKnownHosts(hostsFile string, config *ssh.ClientConfig) {
    key := fleetssh.NewHostKeyFile(hostsFile)
    check := fleetssh.NewHostKeyChecker(key)
    config.HostKeyCallback = check.Check
}

./ssh_config.go:36: cannot use check.Check (type func(string, net.Addr, "github.com/coreos/fleet/Godeps/_workspace/src/golang.org/x/crypto/ssh".PublicKey) error) as type func(string, net.Addr, "golang.org/x/crypto/ssh".PublicKey) error in assignment

It's possible I'm misusing this library somehow, but it seems like the Go vendor experiment that has been adopted in go 1.6 might enable this type of use.

[dongsupark]

I think this issue is already resolved since fleet started using govendor instead of Godeps. As far as I tested it shortly, it's already possible to call methods of github.com/coreos/fleet/ssh, even outside of fleet.
So I'm closing it. Thanks!

[jasonmoo]

Cool I actually went ahead and wrote a slightly more robust version. But glad you guys are making this available.

https://github.com/emptyinterface/knownhosts