WIP: Re-implementing kube-up in go

This is very much a WIP. Wanted to get comments before I get too far down any rabbit holes.

kube-up.go follows the structure of kube-up in util.sh pretty closely. My next step is to take the library stuff currently in kube_updown.go and fit it nicely into the cloudprovider abstraction.

gcloud's config is stored locally. I could find where that is stored and grab it directly.

Right now, I try to grab the project name from:
1. the -project flag
2. the PROJECT environment variable
3. gcloud's local config for default project

If we want to get gcloud out of the mix, we might want to cache our own default project locally. Then consecutive deploy calls wouldn't all need the -project. Thoughts?