fix magnum manage templates

[Spyros Trigazis]

cmd/template_manage doesn't read the configuration from magnum.conf properly.

to test that the configuration is not loaded properly do the following:
change the enabled_definitions in magnum.conf and do list-templates. The output of the command is wrong. These tests should catch it, and we also need to fix template_manage.

[Spyros Trigazis (strigazi)]

Please user cliff and openstack/osc-lib where possible.

The command must have the option --config-file and --config-dir or use the default magnum.conf. This functionality is provided but oslo_config.

NOTE:
if you get into the magnum-template-manage shell, issuing list-templates actually works, but issuing directly "magnum-template-manage list-templates" doesn't work properly.

[Hieu LE (hieulq)]

Hi Spyros, I prefer using cliff with default magnum.conf file.

[Hieu LE (hieulq)]

Seems that there are some problems with Gerrit, below are patch link:
https://review.openstack.org/#/c/353951/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/353951
Committed: https://git.openstack.org/cgit/openstack/magnum/commit/?id=99cfbcbc8bcdb69e75ebd39dc19273da6c64eae5
Submitter: Jenkins
Branch: master

commit 99cfbcbc8bcdb69e75ebd39dc19273da6c64eae5
Author: Hieu LE <email address hidden>
Date: Thu Aug 11 18:10:30 2016 +0700

    Make magnum manage_template read config file and increase coverage

    Currently magnum-manage-template command doesn't read config file
    properly. This patch make manage-template script read config file
    and display template list the right way.

    Add new unit tests for cmd/template_manage.py.
    Increase the coverage for cmd/template_manage.py from 0 to 100%.

    Change-Id: I3a4df33834201148f824ebe013c5a22aee3ec1f8
    Partial-Bug: #1511667
    Closes-Bug: #1612596

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/magnum 3.1.0 release.