Refactor Attacks.IsSquareAttacked, Attacks.IsSquareInCheck

[eduherminio]

Moving stuff to Position and making IsSquareAttackedByX non static, accessing PieceBitBoards directly

8+0.08
Score of Lynx-perf-issquareattackedbypawns-2473-win-x64 vs Lynx 2465 - main: 4658 - 4824 - 5829  [0.495] 15311
...      Lynx-perf-issquareattackedbypawns-2473-win-x64 playing White: 3179 - 1531 - 2945  [0.608] 7655
...      Lynx-perf-issquareattackedbypawns-2473-win-x64 playing Black: 1479 - 3293 - 2884  [0.382] 7656
...      White vs Black: 6472 - 3010 - 5829  [0.613] 15311
Elo difference: -3.8 +/- 4.3, LOS: 4.4 %, DrawRatio: 38.1 %
SPRT: llr -2.27 (-78.4%), lbound -2.25, ubound 2.89 - H0 was accepted

2478 after refactoring IsInCheck

Test  | perf/IsSquareAttackedByPawns
Elo   | 1.88 +- 3.41 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=32MB
LLR   | 2.90 (-2.25, 2.89) [-3.00, 1.00]
Games | N: 24790 W: 7795 L: 7661 D: 9334
Penta | [955, 2880, 4638, 2920, 1002]
https://openbench.lynx-chess.com/test/116/

Test  | 45896CFAF16E6AAA
Elo   | -0.01 +- 2.93 (95%)
SPRT  | 40.0+0.40s Threads=1 Hash=128MB
LLR   | 0.99 (-2.25, 2.89) [-3.00, 1.00]
Games | N: 30504 W: 8658 L: 8659 D: 13187
Penta | [908, 3668, 6088, 3693, 895]
https://openbench.lynx-chess.com/test/118/

> python .\sprt.py -w 8658 -l 8659 -d 13187 -e0 -5 -e1 0
ELO: -0.0114 +- 2.93 [-2.94, 2.92]
LLR: 3.66 [-5.0, 0.0] (-2.94, 2.94)
H1 Accepted