vCloud version API 1.5 requires us to adapt certain calls. This
patch does all the necessary things to scan a vCloud 1.5 completely
and read all the necessary attributes, as we could already before.
Furthermore, it add tests for the version 1.5 calls.
The API version can now be set as a version param to the vcloud
compute resource. By default it chooses version 1.5.
This has been tested against a vCloud 1.5 and 1.0.
Improve the models to work with the current api version. add tests
that use fake-data, that was captured from a real vCloud.
Also removed a couple of dead code. Tests have been added for
everything that changed or have been added. All the existing but
untouched parts have not been tested.