JCLOUDS-670 Option force no password when launching images on providers

Adds the option to override whatever password is given from the provider for the image.

See [jira](https://issues.apache.org/jira/browse/JCLOUDS-670)
Yes, made a small mistake, the second builder.noPassword() should be builder.noPrivateKey obviously.
I don't see the NPE though? The second if statement checks if the string content is empty, something different than the