Fix deprecation messages caused by recent changes to Duration.

Can't `split` just write directly into `TimeVal`? It looks like you did that for the posix version. Edit: oh, looked it up. that is terrible. Kind of reminds me of how people used OO design more because it was 'in' than because it made sense. I think we should actually deprecate `TimeVal`, and just use `Duration` directly instead.

I actually think this fixes a bug, wasn't `timeout.fracSec.usecs` the number of microseconds less than one millisecond?