Added the ability to make a joint histogram from a single source file via unu jhisto.  Providing a single input nrrd results in that nrrd being sliced along the specified axis (0 by default) into as many separate nrrds as bins specified.
Added the ability to make a joint histogram from a single source file via
unu jhisto.  Providing a single input nrrd results in that nrrd being sliced
along the specified axis (0 by default) into as many separate nrrds as bins
specified.



git-svn-id: 9e9401559e51101c165cdce4d49b411eb20436ed@4701 3d70eeeb-363e-0410-a505-8a46323a89f2

BRAINSia/teem,Slicer/teem,Slicer/teem,BRAINSia/teem,Slicer/teem,Slicer/teem,BRAINSia/teem,BRAINSia/teem,Slicer/teem,BRAINSia/teem