some minor modifications; new examples of use added
some minor modifications; new examples of use added

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