Removed hardcoded path within the Gemfile
 * Now using ~ to specify home dir
Updated installation description
 * Now describing how to install in 1.0.z and 1.y.z
Fixed for issue #4
 * An nil user config is not crashing the user parameters command
 * Close #4
Removed a useless method definition
Added and update Vagrantfile used for testing purpose
 * Added a Vagrant.require_plugin('nugrant') clause in v2 files
   so plugin is loaded correctly
 * Added a new empty config file for v2 version
Updated CHANGELOG