The existing documentation example looks intimidating as it includes:
* variable interpolation
* configuration of the chef provisioner
* and it misses the `config_template` file
In the issue comments, [simpler and complete example](https://github.com/hashicorp/packer/issues/3355#issuecomment-198134727) exists already and works out of the box.
This change adds the simpler and complete example, while leaving the more complicated example intact.