Interface for normalization plan.
Performs "normalization" of regions on the cluster, making sure that suboptimal choice of split keys doesn't leave cluster in a situation when some regions are substantially larger than others for considerable amount of time.
Plan which signifies that no normalization is required, or normalization of this table isn't allowed, this is singleton.
Normalization plan to merge regions (smallest region in the table with its smallest neighbor).
Chore that will call
Factory to create instance of
Simple implementation of region normalizer.
Normalization plan to split region.