Adding with_ssh optional approach to puppet provisioner plugin.

Mitchell,

This change is to support the use of scp as a method of pushing resources into the guest VM for the puppet provisioning plugin.  We've added a configuration option (with_ssh) to the plugin.

The changes are coming from work going on in the CloudStack project over at ASF, where we would love to use Vagrant as the method for individual developers to manage their own "cloud in a box" environment.  The reason for this approach, is that we hit was that the Virtual Box Guest Additions don't function when our guest boots into Xen.

Please let us know if you have any further questions, but we would love if you were willing to bring this patch into your next release.

Here's a reference to our discussion on the topic: http://mail-archives.apache.org/mod_mbox/incubator-cloudstack-dev/201207.mbox/%3CCAKprHVZb6VSUVuKJW_P2EKqTFAVH_pe1So7E-prYeCfZSESq9g%40mail.gmail.com%3E

Thanks again, and please let us know if there is anything you would like to see done differently!