First commit of registration scripts

Added scripts to register T1w, AAL label map, and Freesurfer mask
to fMRI space.  Updated README.md to reflect this addition.
NOTES:
Currently using 3d Slicer 3.6.3 splitlabelmap binaries in lib
folder.  Need to deal with getting/building these during enviroment
setup scripts.
Also expects AAL Atlas in aalatlas folder in top level.  Need to
address getting this during setup scripts as well.