Another OSX fix
Another OSX fix

for whatever reason, this hasn't occured so far, but the resulting .so file
gets a suffix to indicate the python version. So we cannot assume the package
to be plainly called _nifty.so

DerThorsten/nifty,DerThorsten/nifty,DerThorsten/nifty,DerThorsten/nifty,DerThorsten/nifty