MetaDataBlast does not need to be loaded at start-up 

Also, this only loads the core module and does not load any plugins that may override it.
For Ensembl Genomes we have to override this module because our BLAST set-up is not compatible with the core module. We can't start our server until we remove this line.
Merge pull request #59 from nicklangridge/bugfix/metadatablast

MetaDataBlast does not need to be loaded at start-up