Added a single warning for running without a CCDS database, and provided an exit for certain no-data situations.
Added a single warning for running without a CCDS database, and provided an exit for certain no-data situations.

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