MGH format: More tweaking
MGH format: More tweaking

Write tag data in the same order as what appears to be performed in the FreeSurfer code: transform matrix, then general tags, then cmdline history.

MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3