Auto-sizing

[LeeCampbell]

Guidance from Gil:

Auto-sizing is another useful thing… Not having to specify an initial range is useful for lazy folks (who are ok with resizing latencies in the recording path). It is also useful as a way to avoid overflowing wrongly-initial-sized histograms: unexpected large values result in a resize rather than an AIOOB exception. If your are ok with taking the latency hit (and potential mem size hit) for that, it's cleaner to code to.