add missing primary key
add missing primary key

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