==================================================================================
       Copyright (c) 2020 Nokia
       Copyright (c) 2020 AT&T Intellectual Property.

   Licensed 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.
==================================================================================

This directory contains the source for the RMR messaging portion of the 
framework.  Specifially:

	message.*
		provides a message class from which the user can extract/set information
		(type, subscription ID, payload, etc.) and provides instance funcitons
		for sending and replying to the message. User programmes will interact
		directly with this.

	msg_component.*
		This is a small type def that allows some of the getter functions in message
		to return a smart pointer to memory which cannot directly be released (e.g
		the payload).   This allows the user programme to declare a variable of type
		Msg_component (which is really a smart pointer with a custom deleter) rather
		than having to understand the needed smart pointer construct for these things.

	messenger.*
		This class provides the direct "wrapper" on top of RMR. It supports 
		high level operations such as Listen and callback management.

	callback.*
		This provides the callback support to messenger (listen) functions.

	default_cb.*
		This module contains any default callback functions which are provided
		by the framework (e.g. health check processing).