OGM-393 Renaming OptionValue into OptionValuePair
OGM-207 Avoiding usage of MongoDBDatastoreProvider#getAssociationStorage() in test helper
OGM-207 Some clean-up
OGM-207 Establishing public OgmSessionFactory interface, providing configureDatastore() on that
OGM-207 Making it configurable whether the same session factory instance is used for all test methods of a test or not
WIP