Refstack_client: Reports misleading error information when the config file has file permission issues

[Rama Krishna Bhupathi]

When running Refstack as in

./refstack-client test -c /home/stack/tempest_region1.conf -v -- --regex tempest.api.identity.v3.test_tokens.TokensV3Test.test_create_token

and if the file /home/stack/tempest_region1.conf is owned by root or some other user and cannot be opened it for any reason , the refstack client claims that "[identity]" is missing in the file . This is highly misleading .

Instead put a a more accurate message "File cannot be opened" or "File Permission Denied"

[Paul Van Eck (pvaneck-z)]

Good catch. I will submit a patch to address this.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/467432
Committed: https://git.openstack.org/cgit/openstack/refstack-client/commit/?id=770acc77652fe07593e8034f2212c732e319f72b
Submitter: Jenkins
Branch: master

commit 770acc77652fe07593e8034f2212c732e319f72b
Author: Paul Van Eck <email address hidden>
Date: Tue May 23 18:17:38 2017 -0700

    Check conf file permission

    Since SafeConfigParser.read doesn't thrown an exception
    when a file can not be opened, we must explicitly check first.

    Change-Id: Ifa5c58e5c30323956a401beae9396ffb0b97dbd9
    Closes-Bug: #1692587