Added various output options for mrregister Added user input checks checked rigid and affine registration
Added various output options for mrregister
Added user input checks
checked rigid and affine registration


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