As suggested it was created the variable KOLLA_SERVICE_NAME to identify
the container service name through PS1 shell variable.
This method it was previously discussed in IRC.
https://goo.gl/k7AdEg
The other option it was usage hostname param in kolla_docker, but
currently docker does not support it due this issue:
https://github.com/docker/compose/issues/2460
The final result is like this:
$ docker exec -it heka /bin/bash
(heka)[heka@kolla-control /]$
$ docker exec -it mariadb /bin/bash
(mariadb)[mysql@kolla-control /]$
More details can be accessed through this link
http://paste.openstack.org/show/493689/
Closes-Bug: #1557454
Change-Id: I6aab8d640a8ebb17baa9d6d4f1edd6e331674713
08b08c78b5