This library provides functionality for the Rackspace Public Cloud by
way of the official pyrax SDK (https://github.com/rackspace/pyrax). At
this time only the cloudservers service is functional. Instances can be
created or deleted. Idempotency is provided on matching instances with
the same name, flavor, image, and metadata values within a given
region.

pyrax usage does require a credentials file written out to hold username
and API key.  See pyrax documentation for details
(https://github.com/rackspace/pyrax/blob/master/docs/pyrax_doc.md)