Allow specification of non-default VPC

[boldandbusted]

The Consul TF Registry module allows this. I think I see what changes were made there, and I hope I can make a PR that holds equivalent changes for this module (and how it uses the Consul module itself). I know that the code in the root of this repo is for "examples" and "testing", but I want to be fully lazy and have it also work for a real production setup as well as for testing purposes. ;)

[brikis98]

It might be better to create another folder under examples that contains a more production-ready module.

[boldandbusted]

See #26. :)

[jasonmcintosh]

#39 should now have this fixed?

[brikis98]

Yes, both examples now allow you to use a non-default VPC.