Update to merge.pl
Added in a new case to the copy method. Now if the Havana gene is a bad biotype (i.e
TEC or artifact) and the Ensembl transcript is CCDS, the Ensembl transcript will not
be copied into the TEC/artifact gene. Instead it will be copied over as an Ensembl only
gene and the TEC/artifact gene will be deleted. Previously in this case the Ensembl CCDS
transcript was copied in and the gene biotype was changed from TEC/artifact to protein_coding.
This caused issues with xrefs to TEC/artifact genes existing in the final Ensembl core db
but not in the Vega db.