Redirect stderr to stdout because some python-config's seem to use stderr.
Redirect stderr to stdout because some python-config's seem to use stderr.

r29181

joshua-cogliati-inl/raven,idaholab/raven,idaholab/raven,joshua-cogliati-inl/raven,idaholab/raven,idaholab/raven,joshua-cogliati-inl/raven,joshua-cogliati-inl/raven,idaholab/raven,joshua-cogliati-inl/raven,joshua-cogliati-inl/raven,idaholab/raven,joshua-cogliati-inl/raven,idaholab/raven