Refactor Intent subsystem to eliminate using FlowRuleBatchOperation

Change-Id: Iee76dac5fa9935713ffc370b34ac47d9286ff351
diff --git a/core/api/src/main/java/org/onosproject/net/flow/FlowRuleOperations.java b/core/api/src/main/java/org/onosproject/net/flow/FlowRuleOperations.java
index 498cc05..84e0b8b 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/FlowRuleOperations.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/FlowRuleOperations.java
@@ -104,6 +104,17 @@
         }
 
         /**
+         * Appends an existing flow rule to the current stage.
+         *
+         * @param flowRuleOperation flow rule operation
+         * @return this
+         */
+        public Builder operation(FlowRuleOperation flowRuleOperation) {
+            currentStage.add(flowRuleOperation);
+            return this;
+        }
+
+        /**
          * Appends a flow rule modify to the current stage.
          *
          * @param flowRule flow rule