Make fetch_by_logic_name() case insensitive.
Make fetch_by_logic_name() case insensitive.

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