CloudSigma2 ComputeService and SecurityGroupExtension

* Added the ComputeService implementation
* Added the SecurityGroup extension
* Added the San Jose region
Nope. In contrast to mockwebserver tests, expect tests don't record the requests. This method returns void, so there's nothing to assert, and due to how the expect tests work, if the method succeeds, that means there is a match between the generated request and the expected one, so the test is fine as-is.