Cloud configs

Started creating some cloud-init/cloud configs for CoreOS.

Example bootup:

```
nova boot --image dd7bc23b-10a9-463b-8d5a-089ecb9aa868 \
                 --flavor onmetal-io1 --key-name main \
                 --user-data script/cloud/coreos-onmetal-io1.yml --config-drive true \
                 tmpnbio
```