ssh-certificate support

[marcvs]

ssh certificates don't seem to be supported. Do you have plans adding them?

[steelbrain]

Hi @marcvs!

We do support ssh certificates, thats what the privateKeyPath (file) and privateKey (buffer) parameters in connect() are for. Have you tried them and found that they don't work?

[marcvs]

Well, I need to add the certificate somewhere, right? I'd need to call connect() with some additional parameter that sends the certifcate (containing the signed pubkey) to the server.

I've consulted my AI, which found that node-ssh and the underlying ssh2 did not support ssh-certificates, too.
I had it implement the necessary changes in ssh2 and node-ssh, and got it working.

Now: If it works without any changes to node-ssh and ssh2 I'd be all the happier.

[marcvs]

I've added a PR for this here #483