Merge into master from pull request #253:

Make the openflow to external timeout as 30 seconds. (https://github.com/floodlight/floodlight/pull/253)

src/main/java/net/floodlightcontroller/devicemanager/internal/AttachmentPoint.java

@@ -28,8 +28,8 @@ public class AttachmentPoint {
 
     // Timeout for moving attachment points from OF/broadcast
     // domain to another.
-    public static final long OPENFLOW_TO_EXTERNAL_TIMEOUT = 5000;  // 5 seconds
     public static final long EXTERNAL_TO_EXTERNAL_TIMEOUT = 5000;  // 5 seconds
+    public static final long OPENFLOW_TO_EXTERNAL_TIMEOUT = 30000; // 30 seconds
     public static final long CONSISTENT_TIMEOUT = 30000;           // 30 seconds
 
     public AttachmentPoint(long sw, short port, long lastSeen) {