add dnac table to test db and more external synonym and go_xref test data
add dnac table to test db and more external synonym and go_xref test data

at7/ensembl,danstaines/ensembl,Ensembl/ensembl,muffato/ensembl,james-monkeyshines/ensembl,mjg17/ensembl,mjg17/ensembl,danstaines/ensembl,james-monkeyshines/ensembl,muffato/ensembl,james-monkeyshines/ensembl,at7/ensembl,muffato/ensembl,james-monkeyshines/ensembl,danstaines/ensembl,Ensembl/ensembl,mjg17/ensembl,willmclaren/ensembl,Ensembl/ensembl,mjg17/ensembl,at7/ensembl,willmclaren/ensembl,muffato/ensembl,at7/ensembl,Ensembl/ensembl