Enabling registration of REAL volumes using Mutual Information measure.  Presently the code is only working for 16-bit volumes (that was used to show PET->MPRAGE prototype).  Solution is to convert to 16-bit correctly while binning the voxel values for the MI.

This is also strongly related to a proper binning for REAL volumes, so it is addressed at the same time along with the corresponding binning interface (Sturges formula) in the registration dialogs.

Finished the parallel variant of Amoeba optimization with x4.5 speed improvement for Rigid transform (bigger gains for higher degree transforms).  See below before and after timing for a single timepoint PET to MPRAGE registration. 

Implemented the Mead-Nedler (simplex\Amoeba) optimization algorithm MDS (multi-direction search) variant.  This is inherently parallel algorithm, presently verified working in the serial workflow.
Presently: inserting parallel instructions to fully utilize MDS parallelism.