updated to handle negative values in location
updated to handle negative values in location

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