provide option for milliseconds

[landroni]

It would be useful to have an option (or provide it by default) for displaying milliseconds, e.g. 12:46:657. Currently Anstop only does 12:46:6. While not terribly useful from a practical perspective, this is more fun, and gives a more continuous and immediate feedback of stopwatch progress.

Other projects like https://github.com/dpadgett/Timer use milliseconds by default.

[landroni]

If you ever go ahead with this feature, I would also suggest to separate seconds from milliseconds with a . (dot). Like this: 12:46.657. IMO this looks less confusing for the user.