Numerical evaluation of zeta and psi functions



Hi,

we have zeta(1.2) -> bfzeta(1.2, 18.0). I propose we make bfzeta
autoload from bffac. Also I propose we do psi[n](x) -> bfpsi(n, x,
18.0) if n is a positive integer and x a float. Also bfpsi should
autoload from bffac.

Andrej