the Neo4jWriter now takes a config xml file. the file allows for a mapping of properties to indices and outside code selection of the Interaction type. additionally support is added for embedded databases to take a neo4j.properties file to start the db.

the Neo4jFactory uses the supplied config to generate the appropriate db instance. The index lookup should be moved out of it though.
moved the index mapping out of the factory into its own service class.
the factory uses only one instance of the indexer.