assign different priorities for different sources for the same data
assign different priorities for different sources for the same data

muffato/ensembl,Ensembl/ensembl,james-monkeyshines/ensembl,muffato/ensembl,muffato/ensembl,mjg17/ensembl,muffato/ensembl,james-monkeyshines/ensembl,mjg17/ensembl,mjg17/ensembl,danstaines/ensembl,danstaines/ensembl,Ensembl/ensembl,Ensembl/ensembl,danstaines/ensembl,mjg17/ensembl,Ensembl/ensembl,james-monkeyshines/ensembl,james-monkeyshines/ensembl