added method to clip sequences on both ends, the length to be clipped is passed as an argument
added method to clip sequences on both ends, the length to be clipped is passed as an argument

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