MNT: Only allow string values in ColSpec
MNT: Only allow string values in ColSpec

danielballan/dataportal,tacaswell/dataportal,ericdill/databroker,NSLS-II/dataportal,NSLS-II/datamuxer,ericdill/datamuxer,danielballan/datamuxer,tacaswell/dataportal,ericdill/datamuxer,NSLS-II/dataportal,danielballan/datamuxer,danielballan/dataportal,ericdill/databroker