Critical Description
With our current implementation of cbtransfer we can extract data for a particular vbucket as csv. For our testing purpose we need to find which vbucket the data set belongs which requires us to run cbtransfer per vbucket. This enhancement request is to give an option to include the vbucket id in the csv output. This would help us track the key and vbucket relation without running the cbtransfer times the number of vbuckets (per node or for the cluster).