Add name attribute in metadata.rb

In Ridley 3.0 ( used in berkshelf 3.0 ) it's mandatory to declare name attribute in cookbook's metadata.rb

The metadata at '/var/folders/mq/3fp1473d3g352rxgb3mksvg80000gp/T/d20140404-25927-100qdtj' does not contain a 'name' attribute. While Chef does not strictly enforce this requirement, Ridley cannot continue without a valid metadata 'name' entry. (Ridley::Errors::MissingNameAttribute)