fixed a bug in the QuantizeIntTo12Bits and QuantizeLongTo12Bits routines and added an improvement that came up in the process of fixing these calls to QuantizeShortTo8Bits namely that if the range of the actual values fits into the target range we only bias and do not rescale to keep as much of the original relations between the values alive
fixed a bug in the QuantizeIntTo12Bits and QuantizeLongTo12Bits routines and added an improvement that came up in the process of fixing these calls to QuantizeShortTo8Bits namely that if the range of the actual values fits into the target range we only bias and do not rescale to keep as much of the original relations between the values alive

git-svn-id: 353be9ac11a1e711854a13efcc2fc17d9d6b83e7@1153 c36c8488-0289-0348-9b64-b301f74bd9a7

BlueBrain/Tuvok,BlueBrain/Tuvok,BlueBrain/Tuvok