Network Graph Refactoring: Northbound API cleanup
 * Renamed/shortened methods:
   Link.getSourcePort() -> getSrcPort()
   Link.getDestinationPort() -> getDstPort()
   Link.getSourceSwitch() -> getSrcSwitch()
   Link.getDestinationSwitch() -> getDstSwitch()

 * Added Javadoc comments

 * Removed deprecated and unused methods:
   Link.getSourceSwitchDpid()
   Link.getSorcePortNumber()
   Link.getDestinationSwitchDpid()
   Link.getDestinationPortNumber()
   NetworkGraph.getOutgoingLinksFromSwitch()
   NetworkGraph.getIncomingLinksFromSwitch()

 * Moved method LinkEvent.getLink(NetworkGraph graph)
   to NetworkGraph.getLink()

Change-Id: Ibedba53fc6cd04d77f508ee67d41b2cfa515d3fc
diff --git a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/SwitchImpl.java b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/SwitchImpl.java
index 97e9004..00f1236 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/SwitchImpl.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/SwitchImpl.java
@@ -52,11 +52,11 @@
 	public Iterable<Switch> getNeighbors() {
 		Set<Switch> neighbors = new HashSet<>();
 		for (Link link : getOutgoingLinks()) {
-		    neighbors.add(link.getDestinationSwitch());
+		    neighbors.add(link.getDstSwitch());
 		}
 		// XXX should incoming considered neighbor?
 		for (Link link : getIncomingLinks()) {
-		    neighbors.add(link.getSourceSwitch());
+		    neighbors.add(link.getSrcSwitch());
 		}
 		return neighbors;
 	}
@@ -64,7 +64,7 @@
 	@Override
 	public Link getLinkToNeighbor(Long neighborDpid) {
 		for (Link link : getOutgoingLinks()) {
-			if (link.getDestinationSwitch().getDpid().equals(neighborDpid) ) {
+			if (link.getDstSwitch().getDpid().equals(neighborDpid) ) {
 				return link;
 			}
 		}