Add support for deleting or clearing all flows:
web/delete_flow.py all
web/clear_flow.py all
diff --git a/src/main/java/net/floodlightcontroller/flowcache/FlowManager.java b/src/main/java/net/floodlightcontroller/flowcache/FlowManager.java
index cce873a..251620c 100644
--- a/src/main/java/net/floodlightcontroller/flowcache/FlowManager.java
+++ b/src/main/java/net/floodlightcontroller/flowcache/FlowManager.java
@@ -751,6 +751,23 @@
     }
 
     /**
+     * Delete all previously added flows.
+     *
+     * @return true on success, otherwise false.
+     */
+    @Override
+    public boolean deleteAllFlows() {
+
+	// Get all flows and delete them one-by-one
+    	ArrayList<FlowPath> allFlows = getAllFlows();
+	for (FlowPath flowPath : allFlows) {
+	    deleteFlow(flowPath.flowId());
+	}
+
+	return true;
+    }
+
+    /**
      * Delete a previously added flow.
      *
      * @param flowId the Flow ID of the flow to delete.
@@ -813,6 +830,23 @@
     }
 
     /**
+     * Clear the state for all previously added flows.
+     *
+     * @return true on success, otherwise false.
+     */
+    @Override
+    public boolean clearAllFlows() {
+
+	// Get all flows and clear them one-by-one
+    	ArrayList<FlowPath> allFlows = getAllFlows();
+	for (FlowPath flowPath : allFlows) {
+	    clearFlow(flowPath.flowId());
+	}
+
+	return true;
+    }
+
+    /**
      * Clear the state for a previously added flow.
      *
      * @param flowId the Flow ID of the flow to clear.