cc_ari_contingency

[PaolaTella]

• cc_ari_contingency() should return a list:

$ ari
$ conf_int

• conf_int possibly with names lower and upper.

• create class ari and print methods to render the output nicier with informative message (see details of the function)

• include warning if sum(mat) < 100 --- see details

[CorradoLanera]

• return:
  $ ari (with confidence interval as attributes)
  $ input
  $ partitions (created with function in back from contingency table #13)
  $ p-values (ari and permutations)