Support a weak read consistency mode for distributed set

Change-Id: I2b72795f083421ecce2c7f7cb932d2ec3e15a960
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultDistributedSetBuilder.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultDistributedSetBuilder.java
index 07b59ad..f7957f3 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultDistributedSetBuilder.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultDistributedSetBuilder.java
@@ -69,6 +69,12 @@
     }
 
     @Override
+    public DistributedSetBuilder<E> withRelaxedReadConsistency() {
+        mapBuilder.withRelaxedReadConsistency();
+        return this;
+    }
+
+    @Override
     public DistributedSetBuilder<E> withPartitionsDisabled() {
         mapBuilder.withPartitionsDisabled();
         return this;