Feature request: multiplication table trainer

[duperray]

Hi,

Thanks you for this excelent game.
My wish would be to train to learn multiplication tables:

• number from 2 to 9
• only 2 slot cages
  Do you think generating a grid like this would be possible (keeping the sudoku rules)?
  I don't know if it would be even possible or fun... but so useful for people like me very bad at multiplicating simple numbers
  but for the first time having fun making so with Gauguin ;)