Merge pull request 'fix_merge_instance' (#26) from fix_merge_instance into master

Reviewed-on: #26

src/main/java/eu/dnetlib/dhp/schema/oaf/Result.java

@@ -706,7 +706,7 @@ public class Result extends OafEntity implements Serializable {
 			return enrichmentResult;
 		}
 		if (enrichmentInstances == null) {
-			return enrichmentResult;
+			return toEnrichInstances;
 		}
 		Map<String, Instance> ri = toInstanceMap(enrichmentInstances);