Method pop_all

include/fplus/queue.hpp:49–55

    }

    std::vector<T> pop_all()
    {
        std::unique_lock<std::mutex> mlock(mutex_);
        const auto result = fplus::convert_container<std::vector<T>>(queue_);
        queue_.clear();
        return result;
    }

    std::vector<T> wait_and_pop_all()
    {