This gem is in fact a Vagrant pluging. By installing this gem, it will be possible to define user specific configuration files that will be merge directly into the Vagrant configuration. This is usefull if you need to share a Vagrantfile to multiple developers but would like to customize some parameters for each users differently.
Gemfile gem 'nugrant', '~> 0.0.11'
install gem install nugrant -v 0.0.11