Numpy cannot form arrays from bits. To convert bit images to numpy,
convert bits to bytes.
From suggestion by Alexander Karpinsky, with thanks.
Fixes gh-350.
This is Christoph Gohlke's test suite from his personal PIL package found
at http://www.lfd.uci.edu/~gohlke/pythonlibs/.
This is just to bring it in as a separate commit. Future commits will align
it with Pillow.