Investigate running gene pool with std::transform with a parallel execution policy

[MarkZH]

https://en.cppreference.com/w/cpp/algorithm/transform https://en.cppreference.com/w/cpp/algorithm/execution_policy_tag_t

This would replace Thread_Limiter/std::counting_semaphore.

Caveat: would it still be possible to control the number of simultaneous games?

[MarkZH]

Would also need a custom iterator to return pairs of iterators for match ups.