Refactored DestinationSet and nextobj for pws.

- Removed the booleans in destination test set and refactored
  it to use a proper enumeration.
- Create a special next objective for pseudowire transport that
  does not pop the tag.
- Install special filtering rules for receiving trafffic for
  pseudowires in all devices.

Change-Id: I665a00d9a766e026d35799fe2f12d56419cb55cd
diff --git a/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java b/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java
index 360afdd..33c71f5 100644
--- a/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java
+++ b/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java
@@ -357,11 +357,14 @@
      * Segment Routing App ID.
      */
     public static final String APP_NAME = "org.onosproject.segmentrouting";
-
     /**
      * The default VLAN ID assigned to the interfaces without subnet config.
      */
     public static final VlanId INTERNAL_VLAN = VlanId.vlanId((short) 4094);
+    /**
+     * The Vlan id used to transport pseudowire traffic across the network.
+     */
+    public static final VlanId PSEUDOWIRE_VLAN = VlanId.vlanId((short) 4093);
 
     /**
      * Minumum and maximum value of dummy VLAN ID to be allocated.