anchor.diff:  - apt-configure
   - package-update-upgrade-install
   - landscape
  +- ntp
   - timezone
   - puppet
   - chef
  
positive.code: 
  cloud_config_modules:
  - emit_upstart
  - disk_setup
  - mounts
  - ssh-import-id
  - locale
  - set-passwords
  
negative.code: - write-files
  - growpart
  - resizefs
  - disk_setup
  - mounts
  - set_hostname
  - update_hostname
  - update_etc_hosts
  