added coverage information to return allele features
added coverage information to return allele features

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