avoid incredibly slow evaluation of hyp2f1 for z ~= -1
avoid incredibly slow evaluation of hyp2f1 for z ~= -1

Alwnikrotikz/mpmath,tectronics/mpmath,thegooglecodearchive/mpmath,Alwnikrotikz/mpmath,upiterbarg/mpmath,tectronics/mpmath,upiterbarg/mpmath,thegooglecodearchive/mpmath