deleted temporary method for PoincarePolynomial
Divisor constructor now sets MatrixOfHyperplaneArrangement

which is a new attribute for divisors
(needs GaussForHomalg v2013.09.20, MatricesForHomalg v2013.09.23)
installed combinatorial polynomials for arrangement divisors

. TuttePolynomial
. CharacteristicPolynomial
. PoincarePolynomial

(needs CombinatoricsForHomalg v2013.09.20)