fix ellippi to return an inf instead of raising an exception (thanks to John Beyers)
fix ellippi to return an inf instead of raising an exception (thanks to John Beyers)

klkuhlm/mpmath,fredrik-johansson/mpmath,JensGrabner/mpmath,JensGrabner/mpmath,klkuhlm/mpmath,bjodah/mpmath,bjodah/mpmath