add the OS_NO_CACHE option to the openstack::auth_file

[Xingchao Yu]

Add the OS_NO_CACHE to the openstack::auth_file ,this is useful when you want to disable the keyring.
And add a spec test for the class openstack::auth_file

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/27069

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/27069
Committed: http://github.com/stackforge/puppet-openstack/commit/03556cd333afaa19f58825789c2429793ec5eff5
Submitter: Jenkins
Branch: master

commit 03556cd333afaa19f58825789c2429793ec5eff5
Author: newptone <email address hidden>
Date: Wed Apr 17 22:40:33 2013 +0800

    Add param use_no_cache to the openstack::auth_file

    Fix bug 1169993

       This patch contains:
          * use_no_cache param will add BooleanVar OS_NO_CACHE to the openrc,
             in the default its value is true.
          * add the openstack_auth_file_spec for test.

    Change-Id: I3885bccb4c06bbe652f7fee1d5db83913d8cd79b