Import rackspace-cloudfiles from labs

This PR imports the `rackspace-cloudfiles` API and `rackspace-cloudfiles-uk/s` providers from the `jclouds-labs-openstack` repository.
https://github.com/jclouds/jclouds/blob/master/providers/ultradns-ws/pom.xml#L42

ex.

```
<jclouds.osgi.import>org.jclouds*;version="${project.version}",*</jclouds.osgi.import>
```