Add commit command

Change-Id: If8ff0ec34f5a187b3585ac0ff98e06fba699f809
diff --git a/src/datastore_access.hpp b/src/datastore_access.hpp
index c7a7ee7..7259273 100644
--- a/src/datastore_access.hpp
+++ b/src/datastore_access.hpp
@@ -23,4 +23,6 @@
     virtual void setLeaf(const std::string& path, leaf_data_ value) = 0;
     virtual void createPresenceContainer(const std::string& path) = 0;
     virtual void deletePresenceContainer(const std::string& path) = 0;
+
+    virtual void commitChanges() = 0;
 };