* added methods to add, remove and update interfaces for vSphere
* added missing method to retrieve the interface
* added existing attribute key to interface (required for modifying, deleting interfaces)
* alias interface's mac to id
missing:
- new model tests
- templates model
- clone
this patch includes a lot of changes and cleanups, exposing more fog
collections/models and rewriting most requests
it includes valuable feedback from endzyme <nick.huanca@gmail.com>