Provide nicer progress logging

[jqmp]

Right now, Bionic users can see the progress of their computation by watching the printed logs. However, the stuff we want to log isn't exactly the same as the stuff users want to see. For logs it's good to be verbose, to make debugging and performance checking easier – e.g., if a task might take a long time, it's good to log the exact start and end times – but that produces a lot of log output that doesn't need to be shown in real time.

Also, for interactive use we don't have to restrict ourselves to append-only text. On a terminal we can update text in place to produce progress meters, etc. In a notebook we have even more options. tqdm might be an interesting place to start here.