Add finalize to clean up file handles to Titan
diff --git a/src/main/java/net/floodlightcontroller/linkdiscovery/internal/TopoLinkServiceImpl.java b/src/main/java/net/floodlightcontroller/linkdiscovery/internal/TopoLinkServiceImpl.java
index b73224e..2dbb338 100644
--- a/src/main/java/net/floodlightcontroller/linkdiscovery/internal/TopoLinkServiceImpl.java
+++ b/src/main/java/net/floodlightcontroller/linkdiscovery/internal/TopoLinkServiceImpl.java
@@ -21,7 +21,8 @@
 	@Override
 	public List<Link> GetActiveLinks() {
 		// TODO Auto-generated method stub
-		return linkStore.getActiveLinks();
+		List<Link> retval = linkStore.getActiveLinks();
+		return retval;
 	}
 
 	@Override
@@ -29,5 +30,4 @@
 		// TODO Auto-generated method stub
 		return linkStore.getLinks(dpid);
 	}
-
 }