extended syntax to include ;type=<dba_type> eg: mysql://ensro@ecs4:3352/ensembl_compara_22_1;type=compara current types are (core, hive, compara, pipeline) (default is hive)
extended syntax to include ;type=<dba_type>
eg: mysql://ensro@ecs4:3352/ensembl_compara_22_1;type=compara
current types are (core, hive, compara, pipeline) (default is hive)

Also changed to a global class instance so that cleanup can be
automatic via  DESTROY method. Deprecated cleanup method.

Ensembl/ensembl-hive,Ensembl/ensembl-hive,Ensembl/ensembl-hive,Ensembl/ensembl-hive