ACCUMULO-3089: Create volume chooser from table properties

It's not public API, but if we're selling it as "You can implement your own policy", it should be (and I would argue we should treat it as such until that is rectified). If there is something that fundamentally doesn't make sense and can't be solved in other ways, let's consider that as a reason for change, but I'd prefer not to see an argument for change based only on "we don't *have* keep it compatible"