How to build:
packer build ubuntu-14.04-amd64.json
You can build box for only one provisioner packer
build -only=virtualbox ubuntu-14.04-amd64.json
build -only=parallels ubuntu-14.04-amd64.json
Add box to local vagrant environment
vagrant box add --name "express42/win2012r2-chef" builds/virtualbox/win2012r2-chef.box