Changed method name from list_stable_dbIDs to list_stable_ids for consistency with the rest of the API. Also minor POD changes.

Minor POD reformatting.

Added more systematically-named list_dbIDs and list_stable_dbIDs to replace list_geneIds and list_stable_geneIds; the old functions are still there for backwards compatibilty but now print a warning and call the appropriate list_ function. Common functionality for list_ functions is in BaseAdaptor.pm.

added mRNA to feature table
CDS is now actually CDS when there is UTR
pseudogenes dump as misc_RNA instead of as CDS