Add TSMgmtConfigFileAdd api doc

doc/developer-guide/api/functions/TSMgmtConfigFileAdd.en.rst

@@ -0,0 +1,43 @@
+.. Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed
+   with this work for additional information regarding copyright
+   ownership.  The ASF licenses this file to you under the Apache
+   License, Version 2.0 (the "License"); you may not use this file
+   except in compliance with the License.  You may obtain a copy of
+   the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+   implied.  See the License for the specific language governing
+   permissions and limitations under the License.
+
+.. include:: ../../../common.defs
+
+.. default-domain:: c
+
+TSMgmtConfigFileAdd
+*******************
+
+Synopsis
+========
+
+.. code-block:: cpp
+
+    #include <ts/ts.h>
+
+.. function:: TSReturnCode TSMgmtConfigFileAdd(const char *parent, const char *fileName)
+
+Description
+===========
+
+This is used to 'attach' a config file to a parent config file. It is meant to be used in the context
+of a plugin but can also be used internally. Using this you can tie a plugin's config file to, for example,
+remap.config. In that instance any changes to the fileName file will trigger a reload of the parent file when
+a config reload is requested.
+
+In the case of a remap.config reload all parent-child file associations are destroyed on reload but plugins are also
+reloaded, so if using it within a plugin the API should be called in a location that will be known to be called on
+plugin initialization.