Add copy command

Change-Id: I0a88f7fa9a096022dd95e8af8854f980ca34f043
diff --git a/src/netconf-client.hpp b/src/netconf-client.hpp
index 143f200..2db21c9 100644
--- a/src/netconf-client.hpp
+++ b/src/netconf-client.hpp
@@ -45,6 +45,7 @@
                     const std::string& data);
     void copyConfigFromString(const NC_DATASTORE target, const std::string& data);
     std::shared_ptr<libyang::Data_Node> rpc(const std::string& xmlData);
+    void copyConfig(const NC_DATASTORE source, const NC_DATASTORE destination);
     void commit();
     void discard();