s3 items are now supported directly in the openshift_hosted role.

* Added checks to make ci for yaml linting
* Modified y(a)ml files to pass lint checks

The variable's name for deleting the temporary file was a bit
missleading, so it has been renamed to be more explicit.

While the path was hardcoded in /root/, which could be problematic when
the playbook is not run as run.

It would be nice to have options to be able to:
* Delete or not the temporary config file - so that it can be check/modified directly
* Create or not the bucket, as you might not have the right to do so

This commit allows both of those things, without changing the default
behavior of the playbook.

  * Added a default function for the lookup.
  * According to [1] added default(,true) to avoid empty string

 [1] https://github.com/openshift/openshift-ansible/blob/master/docs/best_practices_guide.adoc#filters

adhoc s3 registry - add auth part in the registry config sample

File playbooks/adhoc/s3_registry/s3_registry*

To be able to use a different bucket name and region, aws_bucket and aws_region are now available

  * Add variable for region and bucket into j2
  * Update comment Usage
  * Add default aws_bucket_name and aws_bucket_region

Without the auth part, after spawning the registry we were not able to do an auth.

```
docker login -u .. -p ...  172.30.234.98:5000
Error response from daemon: no successful auth challenge forhttp://172.30.234.98:5000/v2/ - errors: []
```

Simply adding this part in the registry config sample