Add possibility to acept matrix A with complex numbers

[jccf19]

To do this. modify plane rotations:

        s = H(j + 1, j) / (sqrt(abs(H(j + 1, j))^2 + H(j, j)^2));
        c = H(j, j) / (sqrt(abs(H(j + 1, j))^2 + H(j, j)^2));