Adding Hiera resource creation

For issue #18. Enables Hiera setup via hashes on the parameters:

- `ufw_allows`
- `ufw_denies`
- `ufw_limits`
- `ufw_loggings`
- `ufw_rejects`

And calling the built-into Puppet `create_resources` function on the respective ufw resources. Backwards compatible (the default empty hashes cause nothing to be created).