Renamed *NetworkGraph* references to *Topology*.

Change-Id: Iec01c47086e1518592c0753e75395d3fe5abcde3
diff --git a/src/main/java/net/onrc/onos/core/topology/Link.java b/src/main/java/net/onrc/onos/core/topology/Link.java
index 8715b12..2bd9cef 100644
--- a/src/main/java/net/onrc/onos/core/topology/Link.java
+++ b/src/main/java/net/onrc/onos/core/topology/Link.java
@@ -3,7 +3,7 @@
 // TODO Everything returned by these interfaces must be either Unmodifiable view,
 // immutable object, or a copy of the original "SB" In-memory Topology.
 /**
- * Interface of Link object in Network Graph topology.
+ * Interface of Link object in the topology.
  */
 public interface Link {
     /**