The new std.process is ready for review

[jerro]

> To me, "asynchronous" implies that something is going on in the 
> background that will produce a result in the future.  That is 
> not what happens here.
>
> I agree that nonBlockingWait() is less than ideal, though, 
> mainly because it is an oxymoron. :)  I considered "status", 
> "isAlive", etc., but I think it is important to emphasise the 
> fact that if the process *has* terminated, nonBlockingWait() 
> has the same, perhaps non-obvious, effects as wait():
>
> On POSIX, it makes the OS clean up after the process.
> On Windows, it closes the process handle.
> On all platforms, it invalidates the processID and osHandle 
> properties of the Pid object.
>
> If you or anyone else have a better suggestion, I'm all ears.
>
> Lars

Maybe tryWait?