Added memoization of data lineage (so caching transformers will work)
Added memoization of data lineage (so caching transformers will work)

tomerk/keystone,tomerk/keystone,kcompher/keystone,tomerk/keystone,tomerk/keystone,amplab/keystone,zhaozhang/keystone,o0neup/keystone,amplab/keystone,kcompher/keystone,zhaozhang/keystone,dongjoon-hyun/keystone,o0neup/keystone,javadba/keystone,amplab/keystone,amplab/keystone,javadba/keystone,dongjoon-hyun/keystone