SSH connection not closed properly

[aardkronkel]

SSH connection needs to be closed when done. This is currently not the case.

Perhaps refactor connector.go and execute.go
and replace ssh.Dial convenience function call with something else:

c, err := net.DialTimeout(network, addr, timeout)
if err != nil {
    return nil, err
}
conn, chans, reqs, err := ssh.NewClientConn(c, addr, config)
if err != nil {
    return nil, err
}

// will close the underlying net.Conn
defer conn.Close 

client := ssh.NewClient(c, chans, reqs)

[aardkronkel]

Solved by adding CloseConnection function in Connector interface. See commit 948610a