pyfits -> astropy.io.fits

[hoyleb]

Hi Mattias!

a pip install on my mac (10.13.2) using conda 4.3.30 and Python 2.7.14 :: Anaconda, Inc. causes an error that can be fixed by changing the (depreciated) pyfits to astropy.io.fits everywhere.

Ben.

[mgckind]

thanks! it's been a while. I'll update it