CORD-349 Support VLAN cross-connect traffic

Change related to this topic:
- Support VLAN cross-connect traffic
    Utilize ports subjectClass to achieve. For non-xConnect port, set interface VLAN to -1
- Remove VLAN checking since we have multiple VLANs per port
- Hash the L2 interface group key generation to include VLAN as well
- Update the network-cfg.json sample

Other refactoring changes:
- Read next objective stores from srManager directly
- Use constant for flow priority
- CORD-267 Javadoc fix

Change-Id: I4ca8c2d9c8b3633a4a0101c5070d19343f7e5b90
diff --git a/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java b/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java
index 44a0a2c..ca283f0 100644
--- a/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java
+++ b/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java
@@ -28,7 +28,7 @@
     private List<GroupBucketIdentifier> bucketIds;
 
     /**
-     * Constructor.
+     * Constructs policy group identifier.
      *
      * @param id unique identifier associated with the policy group
      * @param input policy group params associated with this group