* New yang changelog experimental feature for automatic upgrade

* Added modules-state diff parameter to xmldb_get datastore function for startup scenarios.
* Allowed Yang extended Xpath functions (syntax only):
  * re-match, deref, derived-from, derived-from-or-self, enum-value, bit-is-set
* XSD regular expression handling of dash(`-`)
  *: Translate XDS `[xxx\-yyy]` to POSIX `[xxxyyy-]`.
* YANG Anydata treated same as Anyxml

apps/backend/backend_plugin.c

@@ -156,31 +156,6 @@ clixon_plugin_statedata(clicon_handle    h,
     return retval;
 }
 
-/*! Call configuration upgrade routines in backend plugins
- * @param[in]  h    Clicon handle
- * @param[in]  xms  XML tree of module state differences
- * @retval     0    OK
- * @retval    -1    Error in one (first) of user callbacks
- */
-int
-clixon_plugin_upgrade(clicon_handle       h,
-		      cxobj              *xmodst)
-{
-    int             retval = -1;
-    clixon_plugin  *cp = NULL;
-    upgrade_cb_t *fn;          /* Plugin configuration upgrade fn */
-    
-    while ((cp = clixon_plugin_each(h, cp)) != NULL) {
-	if ((fn = cp->cp_api.ca_upgrade) == NULL)
-	    continue;
-	if (fn(h, xmodst) < 0)
-	    goto done; 
-    }
-    retval = 0;
- done:
-    return retval;
-}
-
 /*! Create and initialize transaction */
 transaction_data_t *
 transaction_new(void)