Port provisioning scripts to Puppet

- Declare ssh keys to be added in `puppet/hieradata/common.yaml` files.
  They use puppet's create resourse syntax. For each key you need to
  defined the owner, type, actual key signature, and status.

Ex: `common.yaml`
```yaml
---
ssh_keys:
    "artur.rodrigues":
        type: "ssh-rsa"
        key: "AAAABB...AQQwggyfood"
        ensure: "present"
    "joao.sa":
        type: "ssh-rsa"
        key: "AAAAB3...5/gSHiggy1k"
        ensure: "present"
```