also has a unigene species-specific source

if the production database value is NULL, we do not overwrite the existing value in the core-like database
this allows us to keep information like db_version which is database specific and should not be centrally held

Added a new option "-v" which will replace the string "####DB_VERSION####" by the value of the parameter "-v", in the introduction text.

[ENSCORESW-399] Fixing an issue reported from Steve Moss. We cause an exception because we do not check if we can project the cDNA location. Sometimes it is undefined.