Implement HumanSolvePossibleSteps. Mainly consisted of moving around lines from the impl of newHumanSolveSearcherSingleStep. i-sudoku, dokugen don't work... but they didn't as of last commit either.
Implement HumanSolvePossibleSteps. Mainly consisted of moving around lines from the impl of newHumanSolveSearcherSingleStep. i-sudoku, dokugen don't work... but they didn't as of last commit either.

jkomoros/sudoku,jkomoros/sudoku,jkomoros/sudoku