New tier0 thread pooling code, should schedule better with less contention, slightly changed API
Lots of API changes here I've replicated to the rest of our code base,
I'd imagine I've fucked at least one thing up though.
Functor jobs are replaced by IThreadPool::QueueJob(WithFlags) which
accepts a std::function, much simpler to use and execute
Delete all this saverestore shit
remove convars: cl_team, cl_class, (versus_)stats_highlight_interval