Dont use a context manager for np.load  This isn't supported in numpy 1.6.
Skip shading of masked array test on numpy 1.6
Don't usea keyword to
git commit . -m Dont use axis keyword to np.linalg.norm. This was not added until numpy 1.8
Merge pull request #3661 from jenshnielsen/numpy_16_fixes

TST : Numpy 1.6 fixes