Fixed Defect:  Certain ANALYZE files which represent ROI are saved with trivial  {Slope,Intercept} tags and were loaded as REAL volumes (64-bit).  Now loading correctly as ROI (1-bit).

Defect correction when attempting to load the unsupported RAW format: provided a graceful exit.

NIFTI\NIFTI1 file format:  enable loading the volumes with (signed) DT_INT8 and DT_INT16 data types.