add stub method get_connections
add stub method get_connections

also made stub methods private until they have implementations

hnunner/PyOpenWorm,travs/PyOpenWorm,mwatts15/PyOpenWorm,openworm/PyOpenWorm,mwatts15/PyOpenWorm,kaustubhcs/PyOpenWorm,gsarma/PyOpenWorm,gsarma/PyOpenWorm,openworm/PyOpenWorm