New progressbar doesn't show elapsed time

[ricardoV94]

Description

This was really neat in the old progressbar, we would get ETA/Elapsed, now we only get ETA (or Elapsed?). Can we have both?

CC @fonnesbeck @rob

[fonnesbeck]

I was using the percentage as elapsed and the time as ETA. Can certainly add more metrics if we want, but was trying to keep it simple.

[ricardoV94]

Percentage doesn't tell you if your run took 1 minute or 2 hours to get to 50% (useful for long sampling when coming back)