[PATCH] Add the stopwatch.stp tapset

[Frank Ch. Eigler]

Hi, Will -

> One thing missing from the simpler API is a way to clean things up.  [...]
> function delete_stopwatch (name:string) {}

OK, good idea.

> probably should have matching optional that can be explicitly called [...]
> function create_stopwatch (name:string) {}

This one sounds like make-work.  It could be that exact empty function, no?

- FChE