http://chef.github.io/bento/
https://github.com/chef/bento

https://atlas.hashicorp.com/bento/boxes/centos-7.2
https://atlas.hashicorp.com/bento/boxes/centos-7.2/versions/2.2.7
https://atlas.hashicorp.com/bento/boxes/centos-7.2/versions/2.2.7/providers/virtualbox.box