[ilgsmblx] Two ways to use chess endgame tablebases

The hard way is to use them as an evaluation function at the leaves of the minimax tree.  Bitbases might be easier.  Either way, many cycle latency of a hash table lookup of memory or disk.

The easy way is only to start using them when the current position may be looked up in the tablebase, abandoning alpha-beta altogether.  Getting to the best endgame remains the job of the traditional evaluation function which, in practice, supposedly does quite well.