Break `project.json` into multiple files in a `.project` directory

[mikeschinkel]

Working with project.json it's becoming clear that it will grow to enormous site and quickly. Further, if might have value for the deployed app, but if deployed it might leak secrets to the outside world.

So I am thinking we should move to a .project directory and then all the top-level objects to be in project.json could instead be their own JSON file. That would allow them to be combined into one project.json for sharing but broken back out for normal use and editing.