Grafana Dashboad creation fails when using alternate overcloud hostnames

[Matt Wisch]

When using alternate overcloud hostnames via a hostname mapping template (like ips-from-pool.yaml) the hosts_to_dictionary function will fail if the server index is not preceded by a hyphen, returning the error: "ValueError: invalid literal for int() with base 10: 'controller01'"

I am proposing a change that will allow both the default server naming index, ie. <cloud>-<function>-##, and alternate naming schemes where the server name ends with a number, but a hyphen does not directly precede the index (or the name does not contain a hyphen at all), ie. <cloud>-<function>### or <function>##

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/355055
Committed: https://git.openstack.org/cgit/openstack/browbeat/commit/?id=b339831ca53ef5f8e6ea88d10f022bb5f8f3c5fb
Submitter: Jenkins
Branch: master

commit b339831ca53ef5f8e6ea88d10f022bb5f8f3c5fb
Author: Matt Wisch <email address hidden>
Date: Fri Aug 12 15:51:12 2016 -0400

    Updated method to index hosts for Grafana Dashboard creation

    Updated the hosts_to_dictionary function to check to see if the last
    digit of the overcloud host name is a digit. If so, it uses a regex
    to isolate the all of the digits at the end of the hostname, and proceeds
    to use that as the dictionary index.

    This change allows for alternate overcloud host naming schemes that do not
    have a hyphen preceding the server number.

    Change-Id: Ief10b2100b5d7c55a940ab4186ce2e31c109420c
    Closes-Bug: #1612787