Removing usage of working_dir from Java workflow node.
introducing ProtoBuffMergingTest
#433 fixing problem with unserializable comparator: moving logic to comparable objects
#433 introducing natural citations ordering
removing empty package
introducing shared citation ExtraData XML model in icm-iis-common, implementing citation importer in mapred_import workflow, implementing exporter module
introducing citations xstream deserialization tests
introducing CitationsXmlConverter unit test
removing json export test which became obsolete