- new sq_pinners
- new pseudo_is_legal() (unfinished)
- improve castling pseudo move gen
- more position and lower level bitboard helper funcs:
- pos_{_occ,between_occ,between_count,pinners}
- bb_{rank,file,rel_rank,_sq_aligned,_sq_between)
- rename some bitboard globals
- replace bb ranks/files enums with defines (issue with clang)
-> Need to find a way to use enum safely
- tests:
- add common-test.h
- new attack-test.c
- bitboard.c: make attacks for knight/king
- square macros (BB, BBfile, BBrank) renamed sq_make, sq_file,
sq_rank, moved to board.h (and become temporarily inline funcs)
- different macros/defs moved to "correct place" (bitboard/board/piece):
board.[ch]: everything related to board/square
bitboard.[ch]: everything related to bitboards
piece.[ch]: everything related to pieces
