Add heat user to HA Mysql

Adding the heat mysql database user to the ha mysql nodes.  This gets around the following error we had with the nova network controller when it pointed to a ha mysql instance:
    Error: /Stage[main]/Heat::Db/Exec[heat-dbsync]: Failed to call refresh: heat-manage --config-file /etc/heat/heat.conf db_sync  returned 1 instead of one of [0]

Also sneaking a change to default HA Mysql IP's for illustrative purposes (rather than required values).