RFC: Dynamic groups support

[Dmitry Chuyko]

....
>
> On these grounds, I'm still standing on my initial suggestion.
> Additional point of frustration is the rounding itself. What is the
> semantics of this code?
>
>     @Threads(1)
>     class T {
>      @GMB @Group @GroupThreads(0.2)
>      void testA() {}
>
>      @GMB @Group @GroupThreads(0.8)
>      void testB() {}
>    }
>
> Should it run only the single thread, associated randomly with testA or
> testB? Should it be biased to become testB? What if there are two
> threads? Three? Four? Six? Should we search for some thread number which
> fits these ratios exactly? Absolute counts evade these tricky questions.
Agree. Should it also be required Sum(@GroupThreads|group)<=@Threads if 
latter specified?

Dmitry
>
> Thanks,
> -Aleksey.