Wrong number of nodes: Messaging service in High Availability Guide

[Peng, Zhang]

This bug tracker is for errors with the documentation, use the following as a template and remove or add fields as you see fit. Convert [ ] into [x] to check boxes:

- [x] This doc is inaccurate in this way:
In Chapter: Messaging service for high availability

During the following section, a 2-node rabbitmq cluster is configed:

"Production servers should run (at least) three RabbitMQ servers for testing and demonstration purposes, however it is possible to run only two servers. In this section, we configure two nodes, called rabbit1 and rabbit2."

but, during the following section when we edit the openstack config file, a 3-node cluter is used:
"transport_url = rabbit://RABBIT_USER:RABBIT_PASS@rabbit1:5672,
RABBIT_USER:RABBIT_PASS@rabbit2:5672,RABBIT_USER:RABBIT_PASS@rabbit3:5672"

We should use a 2-node cluster in openstack config files, too.

- [ ] This is a doc addition request.
- [x] I have a fix to the document that I can paste below including example:
"transport_url = rabbit://RABBIT_USER:RABBIT_PASS@rabbit1:5672,
RABBIT_USER:RABBIT_PASS@rabbit2:5672"

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-----------------------------------
Release: on 2018-01-19 10:34
SHA: 776b0645716960fc5d64821b807a89bd5d344774
Source: https://git.openstack.org/cgit/openstack/openstack-manuals/tree/doc/ha-guide/source/shared-messaging.rst
URL: https://docs.openstack.org/ha-guide/shared-messaging.html

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/545746

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/545746
Committed: https://git.openstack.org/cgit/openstack/openstack-manuals/commit/?id=b8cc1962afdbf7c99e6a0a46a03bd6f175a11aa0
Submitter: Zuul
Branch: master

commit b8cc1962afdbf7c99e6a0a46a03bd6f175a11aa0
Author: Masaaki Kato <email address hidden>
Date: Mon Feb 19 11:53:43 2018 +0900

    Wrong number of nodes: Messaging service in High Availability Guide

    Fix rabbitmq number to 2node
    Closes-bug: #1744646

    Change-Id: I5832006b3faa92f09ae1ae7e45dbdd4c7a9df05d