Fail if required key information can't be found

[hartmantis]

No description provided.

[hartmantis]

@jjasghar With the change in #86, this line will always evaluate to true because it's testing whether the symbol :private_key_path exists, rather than whether that key exists in the config hash.

This would, I think, cover the issue the user reported using Kitchen's configuration methods to

• Fail if no private key path can be found
• Fail if neither a public key nor a name of a key in OpenStack can be found

Does that sound right? It assumes use of SSH (i.e. won't work with Windows VMs) but that assumption already exists in other places that would need to be reworked to add Windows support.

[jjasghar]

👍 yeah that's much better.