Added sudoku example (overlapping alldiffs)
Added sudoku example (overlapping alldiffs)

jjdekker/libminizinc,nathanielbaxter/libminizinc,nathanielbaxter/libminizinc,jjdekker/libminizinc,nathanielbaxter/libminizinc,tias/libminizinc,jjdekker/libminizinc,nathanielbaxter/libminizinc,jjdekker/libminizinc,tias/libminizinc