Added filter for lab of origin.

Works for miRNA and methylation, but not mRNA. This column is missing from the metadata, and the original metadata file (https://www.synapse.org/#!Synapse:syn2278178/) does not have the column `Originating Lab ID` either.

Jira bug created for this (https://sagebionetworks.jira.com/browse/PCBC-14), but will require some other work to pull the correct data in a streamlined fashion from the master cell line metadata file or Synapse table..