Added documentation, fixed some minor bugs/typos

db_operations.php

@@ -263,6 +263,10 @@ if (strlen($db) && (! empty($db_rename) || ! empty($db_copy))) {
         }
     }
 
+    /**
+     * Database has been successfully renamed/moved.  If in an Ajax request, 
+     * generate the output with {@link PMA_ajaxResponse} and exit
+     */
     if( $GLOBALS['is_ajax_request'] == true) {
         $extra_data['newname'] = $newname;
         $extra_data['sql_query'] = PMA_showMessage(NULL, $sql_query);