Step toward transactional API support on DocTree

for ONOS-7237

Change-Id: I021b20c8aac97f96c2ab0e8bc763aa821dc09643
diff --git a/core/api/src/main/java/org/onosproject/store/primitives/NodeUpdate.java b/core/api/src/main/java/org/onosproject/store/primitives/NodeUpdate.java
index 5c21338..8562401 100644
--- a/core/api/src/main/java/org/onosproject/store/primitives/NodeUpdate.java
+++ b/core/api/src/main/java/org/onosproject/store/primitives/NodeUpdate.java
@@ -28,7 +28,7 @@
 import org.onosproject.store.service.DocumentPath;
 
 /**
- * Map update operation.
+ * DocumentTree node update operation.
  *
  * @param <V> map value type
  */
@@ -38,6 +38,8 @@
      * Type of database update operation.
      */
     public enum Type {
+        // FIXME revisit these, mismatch in description and actual implementation
+        // Also, type of update operations probably insufficient.
         /**
          * Creates an entry if the current version matches specified version.
          */