Better error handling in pseudowire implementation.

I refactored the pw handler to return meaningful very specific
errors for failures. As a result, I modified also the cli and rest
api implementations to use these fine grain errors accordingly.

Change-Id: I2429532f747c4560378c40be325b039ca0f5c925
diff --git a/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java b/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java
index c329d3d..b688726 100644
--- a/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java
+++ b/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java
@@ -128,11 +128,15 @@
     L2TunnelHandler.Result addPseudowire(L2TunnelDescription tunnel);
 
     /**
-     * Adss a set of pseudowires.
+     * Adds a set of pseudowires.
+     *
+     *
      * @param l2TunnelDescriptions The pseudowires to add.
      * @return SUCCESS if ALL pseudowires can be instantiated and are deployed, or a
      *         a descriptive error otherwise, without deploying any pseudowire.
+     * @deprecated onos-1.12 use addPseudowire instead
      */
+    @Deprecated
     L2TunnelHandler.Result addPseudowiresBulk(List<DefaultL2TunnelDescription> l2TunnelDescriptions);
 
     /**