Extend `bundle --without` groups on Engine Yard deploy.

eydeploy.rb

# This monkeypatches engineyard-serverside to specify `--without` options for
# `bundle install` on Engine Yard deployment. It supercedes the instructions in
# this doc, which are currently outdated:
#
#   http://docs.engineyard.com/bundler-tips-for-cloud.html
#
# More helpful is this one, which leads us to where the code can be found to
# override:
#
#   http://docs.engineyard.com/customize-your-deployment.html#second
# 
class ::EY::Serverside::Deploy::Configuration
  def bundle_without
    'development test mac'
  end
end