optimize annotation deletion from organism or use script

[nathandunn]

Deleting annotations from an organism as called from this service:

https://github.com/GMOD/Apollo/blob/master/docs/web_services/examples/groovy/delete_annotations_from_organism.groovy

calls this service:

https://github.com/GMOD/Apollo/blob/master/grails-app/services/org/bbop/apollo/OrganismService.groovy#L58

This piece of code is very slow. It should be replaced with code that does, roughly replicating this code-set https://github.com/GMOD/Apollo/blob/master/scripts/delete_features.sh

It should:

• delete feature properties from relevant annotations
• delete feature relations from relevant annotations
• delete feature events from relevant annotations
• delete features, finally