Add initial resources.md for discussion

The first draft of a Kubernetes resource model.
I think the implementation should be free to set any limit it wants greater than the request.  For example, if a user asks for 3 cpu, and a machine has 2 sockets with 4 cpu per socket, then the implementation should be free to set the limit to 4cpus rather than 8, if this serves to help with cache isolation, for example.  The same argument can be made for memory and  NUMA  performance issues.