added make_board and #dirs to piece classes
added sliding pcs move possibilities
added moves for stepping pcs
correcting dirs
made #valid_moves for pawn
created GameBoard#checked? <--major thing
added checked? and valid_move? to board class and deep_dup
set pieces on board
added display_char attributes to piece classes
added GameBoard#display
fixed display to be mapped
chess indices map to board coords
pawn moves validated
need to refactor and implement check mate
added check mate. need refactoring