S9 LIB  (group list integer)  ==>  list

Group the elements of LIST in tuples of INTEGER elements
each (except for the last tuple, which may contain fewer
elements). Return a list of the resulting tuples. The
elements appear in the output list in the same order as
in the input list.

INTEGER must be positive.

(group '(1 2 3 4 5) 2)  ==>  ((1 2) (3 4) (5))
(group '(1 2 3 4 5) 5)  ==>  ((1 2 3 4 5))
