First pass at a great workflow RFC to rule them all.

I don't mind supporting this if people like it and want to see it continue to exist. On the other hand, I think there's demand for managing 3rd party dependencies like berks does, but without forcing you to eat the rest of the berks workflow. I believe (and @jtimberman correct me if I'm wrong) that this was one driver for us to start using berks as part of our tooling to manage Hosted. What I had in mind for Policyfiles w/ a monolithic repo is you'd write Policyfile.rb like:

```ruby
name "chatserver"
run_list "role1", "recipe1", "role2", "etc"

default_source :chef_repo

# Opt-in to community cookbook for "erlang"
cookbook "erlang", artifactserver: "https://supermarket.getchef.com"
```
There's plenty of tricky details there (dependencies) but the basic way it operates should be clear.