bug fixes, general code cleanup and improved performance

optimizations (fixed bugs, improved speed and general code cleanup)

* implemented parallel perft()
* code cleanup
* implemented stuck piece detection (except for pawns)
* trapped pieces score less
* fixed broken "go perft n"
* renamed to greek letters
* fixed alpha/beta pruning
* hashtable is now concurrent collection
* mended some tests + updated opening book

improved time management

v0.9.0

bumped version

bugfixes, performance, better scoring + "go perft"

bugfixes + performance; improved scoring; perft

* fixed possible bug in PV calc
* implemented "go perft <depth>" command
* improved scoring
* code review
* fixed PGN parsing with simple pawn move + promotion

FEN export

v0.7.0

implemented FEN export + added to "pretty print" of board

bug fixes (e.g. white looking at black's clock)

v0.6.0

fixed bug causing white to play on black's time limit

zobrist hashing

Only used for the opening book, but soon for move evaluation.

beating the author

Significant performance improvements + some bugs fixed. I set out to build an engine than could beat me. I have succeeded.

"mate in ..." detection + reporting

v0.3.0

implemented "mate in ..." detection/reporting

improved performance + no illegal moves

v0.2.0

improved performance + no illegal moves

v0.1.0

First "working" version, accepted by Cute Chess and not making (too many) illegal moves.