jimmycuadra/vagrant-librarian-chef — pull request #25 by emyl (2014-07-15 09:40:08+00:00)
Title: Ensure Vagrant can properly merge multiple configurations

In my humble opinion it would be better to use the canonical way for defining configuration variables.

According to [Vagrant docs](http://docs.vagrantup.com/v2/plugins/configuration.html), `UNSET_VALUE` is used for ensuring correct Vagrantfile merge-logic.