Nosleep

[zamar]

Clear gain with 16 threads. Again results vary highly depending on hardware, but on average it's a clear gain.

ELO: 12.17 +-4.3 (95%) LOS: 100.0%
Total: 7998 W: 1407 L: 1127 D: 5464

[mcostalba]

Great Joona! Another SMP big shot :-)

BTW this also paves the way to use std::condition_variable_any instead of
my homegrown hack in thread_win32.h, indeed std::condition_variable_any is
a bit slower, but now that sleeping is out of the hot path, this should be
not measurable anymore.

[zamar]

Yes Marco,

This is the idea. We should be able to use std::mutex and std::condition_variable after this, because they are no longer involved in the hot path...

[glinscott]

Awesome stuff Joona! Merge away :).