Prophet4 rewrite status 2/16/20

Added a simple depth first search. The search uses the alpha/beta algorithm and recognizes checkmated and stalemated positions but otherwise has no “intelligence.” It is a simple fixed depth search without iterative deepening or timing.

The next phase of work will be to add some basic move ordering, such as trying the previous PV first, MVV/LVA capture scoring and killer moves.

The JNI integration with chess4j has gone extremely well. chess4j is capable of using Prophet for search, so after this rewrite is complete there will likely be a chess4j bundle that includes P4 for some platforms. I am leaning towards keeping P4 as a lightweight, XBoard compatible “calculation engine” and leveraging chess4j for ancillary functions such as opening book, pondering support, and distributed computing support.