added title as lookup_key to ExperimentType class in types/__init__.py
added title as lookup_key to ExperimentType class in types/__init__.py

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