metadata.tsv relationship type column improvements
metadata.tsv relationship type column improvements

hms-dbmi/fourfront,hms-dbmi/fourfront,4dn-dcic/fourfront,4dn-dcic/fourfront,4dn-dcic/fourfront,hms-dbmi/fourfront,hms-dbmi/fourfront,hms-dbmi/fourfront,4dn-dcic/fourfront