REST API for pseudowire addition / deletion.

Refactored pseudowire code to use REST in order
to add or delete pseudowires individually. Previous implementation
used the network configuration, which is now completely
removed from the code. Further, I re-organized the code
and create a utility class that holds all the necessary
functionality for verifying pseudowires.

Further, I removed all mastership checks in the pw code
since now a specific pseudowire creation is sent to a single
instance, which will handle the call.

Change-Id: I1eb5e7cc7730ad792ea84dd389475768153e2b68
diff --git a/apps/segmentrouting/web/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java b/apps/segmentrouting/web/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java
index abfba3c..cebcf84 100644
--- a/apps/segmentrouting/web/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java
+++ b/apps/segmentrouting/web/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java
@@ -26,7 +26,6 @@
 import javax.ws.rs.DELETE;
 import javax.ws.rs.GET;
 import javax.ws.rs.POST;
-import javax.ws.rs.Path;
 import javax.ws.rs.Produces;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
@@ -37,7 +36,7 @@
 /**
  * Query, create and remove segment routing plicies.
  */
-@Path("policy")
+// @Path("policy")
 public class PolicyWebResource extends AbstractWebResource {
 
     private static final PolicyCodec POLICY_CODEC = new PolicyCodec();