Proposal: Describe possible project structure and implications

Initial thoughts around scoping Kubernetes resources to projects and the associated implications.

Intended as a complement to #891, but with more detail on the implementation consequences of project scoping throughout the stack.

Would like to get general agreement on an outline to proceed against to support an initial prototype in next couple weeks.
I got curious.
I put 250K keys under 1 etc directory, 60B value per key.  So, 15MB of values which blows up to 30MB of text as a json response. 
curl'ing this takes 1.5s wall time.
All that seems reasonable.
What surprised me is that RSS of etcd was 628MB.  

Might be:
https://github.com/coreos/etcd/issues/162