Adds error checking to loading of metatype in Datas.py (needed to handle differences in numpy type support by platform).
Adds error checking to loading of metatype in Datas.py (needed to handle
differences in numpy type support by platform).

Closes issue #59

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