Added salt-cloud support for Rackspace OpenStack servers.

[andrew-vant]

No description provided.

[gravyboat]

Good stuff, thanks! Do you plan to add support for other OSs?

[andrew-vant]

(assuming I should expand that as OpenStack rather than Operating System) I wasn't planning on it; I did this mostly because I work at RS and had a need for the functionality.

Looking through the docs, it doesn't look like it would be difficult to generalize to other providers. One could do something similar to the package map to provide useful vendor-specific defaults, for settings like identity_url, compute_name, and others. Let the user specify their openstack vendor in pillar and then jinja figures out the rest.

I might retool it that way just for perfectionism's sake, but I have no easy way of testing against anything other than RS.