Cloud Networking

PR for Rackspace networking. Unfortunately, it looks like none of the Rackspace operations for this service can be delegated to the Openstack Neutron code due to differences in URLs and `Network` objects.

- [x] Networks
 - [X] Operations
 - [X] Unit Tests
 - [x] Acceptance Tests
- [x] Virtual Interfaces
 - [X] Operations
 - [X] Unit Tests
 - [x] Acceptance Tests 
Nope. Relic of testing why the endpoint was returning a 403. Turns out it was the wrong endpoint.