Sparkline progress bars

[indigoviolet]

I have seen #1002 , but I think sparklines aren't quite as complex graphics. See https://github.com/holman/spark for example.

It would be nice to be able to track multiple counters during the execution of a program (for example let's say you're hitting a rate limited API, you want to see your qps), and sparklines are well suited to this. They could be two-dimensional progress bars.