recipes/conf_files.rb: delete existing configuration files if they are not required
recipe/conf_files.rb: use conf_files_user attribute for configuration file directories owner instead of "root"
Add ChefSpec tests
Fix ohai 7 plugin "provides" unsupported operation warning
.kitchen.yml: add forwarded ports
Fix ohai 7 plugin "provides" unsupported operation warning (2):

* Remove "provides" call from collect_data.
Add Serverspec tests
kitchen.yml: removed not supported platforms