Adding Vagrant Cloud definition file
Adding Packer definitions and support files for CentOS 7
EL7 has different interface network-names
EL7 requires a VMware Tools patch

Because of this, we need to leave the ISO uploaded by Packer hanging
around for a re-installation stop-gap until VMware issues an update.
Updating Puppet version
Merge pull request #24 from sschneid/centos-7

Add CentOS 7 support