Configure DevStack using new plugin

[venkatamahesh]

http://docs.openstack.org/developer/heat/getting_started/on_devstack.html#configure-devstack-to-enable-ceilometer-if-using-alarms

In this for enabling services instead of enabling each one, we can enable using "enable_plugin ceilometer https://git.openstack.org/openstack/ceilometer".
By doing this we can enable ceilometer services in single step , because by default all services are enabled when we enable plugin.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/222962

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/222962
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=ef2c4f9c1c61edb6c7183062ef73610c060be164
Submitter: Jenkins
Branch: master

commit ef2c4f9c1c61edb6c7183062ef73610c060be164
Author: venkatamahesh <email address hidden>
Date: Mon Sep 14 10:25:22 2015 +0530

    Enable ceilometer services using new plugin model

    when we enable ceilometer using plugin model, by default
    all ceilometer services are enabled. so I replaced the
    lines which will enable services with ceilometer
    plugin model

    Change-Id: I9a048f970441809d5062a59002c36e5c2ad2c667
    Closes-Bug: #1494581