Summarising an ObjectStore

Before releasing a webapp for a completed database build various aspects of the data are 'summarised' This step counts the number of objects of particular classes, identifiers any empty references/collections and collects values to be appear in dropdowns in the query builder and templates.

The latter is configurable, to select those fields that onlt have a few possible values and should be shown in a dropdown.

An example from trunk/bio/tutorial/malariamine/dbmodel/resources/objectstoresummary.config.properties:

max.field.values = 10
org.flymine.model.genomic.Chromosome.fields = primaryIdentifier
org.flymine.model.genomic.DataSet.fields = title
org.flymine.model.genomic.DataSource.fields = name
org.flymine.model.genomic.InfoSource.fields = title
org.flymine.model.genomic.Location.fields = endPhase phase strand
org.flymine.model.genomic.Organism.fields = abbreviation genus name name genus shortName shortName species taxonId
org.flymine.model.genomic.Synonym.fields = type
org.flymine.model.genomic.GOAnnotation.fields = qualifier