Ready: Strong consistency update

- [x] Configs in `advanced.config`
- [x] `riak-admin` interface for ensemble
- [x] Implementation details

Heads up to @andrewjstone, @engelsanchez, and @jtuple when he's back.
This seems to be our current recommendations: http://docs.basho.com/riak/2.0.0/ops/building/planning/cluster/#Ring-Size-Number-of-Partitions