[Feature Request] Add milliseconds as unit

[BlackRose01]

Hey,

I hope this is only a small request. I used your package to schedule refreshes of a meshcat instance. The problem is that the unit second(s) is too big and other packages like multiprocessing or threading won't work. So my question is if it is possible to add the unit "milliseconds"?

Thanks in advance.

KR, BlackRose01