An RFC to standarize on two workflows

This RFC proposes two workflows as "supported", and abstracts
as much of their differences as possible through the use of
additional generators and functionality in the 'chef' command.

If accepted, this RFC would also serve as a guide for tool makers,
as to what the requirements are for maximum converage in the Chef
community.

While other workflows are possible, this RFCs job is to say which
ones we support officially.
Since we're talking about workflows, a nice thing about using JSON, e.g., roles, is that the `knife diff` command works with JSON, but not ruby DSL. This is an essential part of our internal workflow of "make change to .json, knife diff, reconcile unrecognized differences, knife upload."