On python-tripleoclient the tests fail if running without root user.

Currently the tests fail on master if running without root user, because we try to create a symlink on the system:

=========================
Failures during discovery
=========================
--- import errors ---
Failed to import test module: tripleoclient.tests.v1.tripleo.test_tripleo_deploy
Traceback (most recent call last):
  File "/home/hobbestigrou/python-tripleoclient/.tox/py27/lib/python2.7/site-packages/unittest2/loader.py", line 456, in _find_test_path
    module = self._get_module_from_name(name)
  File "/home/hobbestigrou/python-tripleoclient/.tox/py27/lib/python2.7/site-packages/unittest2/loader.py", line 395, in _get_module_from_name
    __import__(name)
  File "tripleoclient/tests/v1/tripleo/test_tripleo_deploy.py", line 30, in <module>
    from tripleoclient.v1 import tripleo_deploy
  File "tripleoclient/v1/tripleo_deploy.py", line 92, in <module>
    class Deploy(command.Command):
  File "tripleoclient/v1/tripleo_deploy.py", line 119, in Deploy
    '/usr/local/bin/' + ansible_playbook_cmd)
OSError: [Errno 13] Permission denied

Failed to import test module: tripleoclient.tests.v1.tripleo.test_tripleo_upgrade
Traceback (most recent call last):
  File "/home/hobbestigrou/python-tripleoclient/.tox/py27/lib/python2.7/site-packages/unittest2/loader.py", line 456, in _find_test_path
    module = self._get_module_from_name(name)
  File "/home/hobbestigrou/python-tripleoclient/.tox/py27/lib/python2.7/site-packages/unittest2/loader.py", line 395, in _get_module_from_name
    __import__(name)
  File "tripleoclient/tests/v1/tripleo/test_tripleo_upgrade.py", line 24, in <module>
    from tripleoclient.v1 import tripleo_upgrade
  File "tripleoclient/v1/tripleo_upgrade.py", line 18, in <module>
    from tripleoclient.v1.tripleo_deploy import Deploy
  File "tripleoclient/v1/tripleo_deploy.py", line 92, in <module>
    class Deploy(command.Command):
  File "tripleoclient/v1/tripleo_deploy.py", line 119, in Deploy
    '/usr/local/bin/' + ansible_playbook_cmd)
OSError: [Errno 13] Permission denied

Failed to import test module: tripleoclient.tests.v1.undercloud.test_deploy
Traceback (most recent call last):
  File "/home/hobbestigrou/python-tripleoclient/.tox/py27/lib/python2.7/site-packages/unittest2/loader.py", line 456, in _find_test_path
    module = self._get_module_from_name(name)
  File "/home/hobbestigrou/python-tripleoclient/.tox/py27/lib/python2.7/site-packages/unittest2/loader.py", line 395, in _get_module_from_name
    __import__(name)
  File "tripleoclient/tests/v1/undercloud/test_deploy.py", line 21, in <module>
    from tripleoclient.v1 import undercloud_deploy
  File "tripleoclient/v1/undercloud_deploy.py", line 19, in <module>
    from tripleoclient.v1.tripleo_deploy import Deploy
  File "tripleoclient/v1/tripleo_deploy.py", line 92, in <module>
    class Deploy(command.Command):
  File "tripleoclient/v1/tripleo_deploy.py", line 119, in Deploy
    '/usr/local/bin/' + ansible_playbook_cmd)
OSError: [Errno 13] Permission denied

So the solution it's run a first time with root user to create the symlink, then tests can be run with normal user. A simple workaround is check the user is root before try create the symlink.