Support for a distributed counter

Change-Id: I346e9baa28556fac13e53771021f5f6fbcd75ac9
diff --git a/core/api/src/main/java/org/onosproject/store/service/StorageService.java b/core/api/src/main/java/org/onosproject/store/service/StorageService.java
index 5ea0420..91cc273 100644
--- a/core/api/src/main/java/org/onosproject/store/service/StorageService.java
+++ b/core/api/src/main/java/org/onosproject/store/service/StorageService.java
@@ -16,6 +16,7 @@
 
 package org.onosproject.store.service;
 
+
 /**
  * Storage service.
  * <p>
@@ -55,6 +56,13 @@
     <E> SetBuilder<E> setBuilder();
 
     /**
+     * Creates a new AtomicCounterBuilder.
+     *
+     * @return atomic counter builder
+     */
+    AtomicCounterBuilder atomicCounterBuilder();
+
+    /**
      * Creates a new transaction context.
      *
      * @return transaction context