[WIP] AWS VPC module improvements

I started wrapping the boto VPC API and realized that I have no idea what should be exposed and what shouldn't.
I'd like that you guys and @colinbjohnson to review this PR and https://boto.readthedocs.org/en/latest/ref/vpc.html and tell me what should I expose.
This module is not tested at all. Can you guys provide instructions on how to test this?
Should I be using moto? Does salt have an AWS environment where the integration tests can run?
The expectedFailure is useful since if it will succeed you guys will not forget to remove the decorator. I believe I fixed the filtering with moto so next version should be fine.
I can add a skipIf that will check if the moto version is greater then the currently released one.