ENH: Update GLCM baseline, using log2
ENH: Update GLCM baseline, using log2

Updated the matlab code to generate the GLCM baseline using log2
for entropy calculations instead of log:
https://github.com/naucoin/radiomics-matlab/commit/6b3aaa472e80ebaf52900d996926d7bd7f060c40
as per comments on:
https://github.com/Radiomics/pyradiomics/pull/77
After this change, tests run on the trunk only have two failures in glcm:
brain2 SumSquares
breast1 SumSquares
TODO: compare these failures against the changes in the branch from:
https://github.com/Radiomics/pyradiomics/pull/80

Issue #56

Radiomics/pyradiomics,Radiomics/pyradiomics,Radiomics/pyradiomics,Radiomics/pyradiomics