Missing auth_url for senlinclient when using senlin-dashboard

I have installed senlin-dashboard and get this error when access to Cluster tab:

```
[Thu Nov 29 01:55:39.547938 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] HTTP exception with no status/code
[Thu Nov 29 01:55:39.547979 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] Traceback (most recent call last):
[Thu Nov 29 01:55:39.547986 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/lib/python2.7/dist-packages/openstack_dashboard/api/rest/utils.py", line 127, in _wrapped
[Thu Nov 29 01:55:39.547991 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] data = function(self, request, *args, **kw)
[Thu Nov 29 01:55:39.547996 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/local/lib/python2.7/dist-packages/senlin_dashboard/api/rest/senlin.py", line 141, in get
[Thu Nov 29 01:55:39.548001 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] request, filters=filters, **kwargs)
[Thu Nov 29 01:55:39.548006 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/local/lib/python2.7/dist-packages/senlin_dashboard/api/senlin.py", line 233, in profile_list
[Thu Nov 29 01:55:39.548012 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] profiles_iter = senlinclient(request).profiles(**params)
[Thu Nov 29 01:55:39.548016 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/lib/python2.7/dist-packages/horizon/utils/memoized.py", line 95, in wrapped
[Thu Nov 29 01:55:39.548021 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] value = cache[key] = func(*args, **kwargs)
[Thu Nov 29 01:55:39.548026 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/local/lib/python2.7/dist-packages/senlin_dashboard/api/senlin.py", line 90, in senlinclient
[Thu Nov 29 01:55:39.548031 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] region_name=request.user.services_region)
[Thu Nov 29 01:55:39.548036 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/local/lib/python2.7/dist-packages/senlinclient/v1/client.py", line 23, in __init__
[Thu Nov 29 01:55:39.548051 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] **kwargs)
[Thu Nov 29 01:55:39.548056 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/local/lib/python2.7/dist-packages/senlinclient/plugin.py", line 88, in create_connection
[Thu Nov 29 01:55:39.548061 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] app_version=app_version, **kwargs)
[Thu Nov 29 01:55:39.548066 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/lib/python2.7/dist-packages/openstack/connection.py", line 306, in __init__
[Thu Nov 29 01:55:39.548071 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] **kwargs)
[Thu Nov 29 01:55:39.548076 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/lib/python2.7/dist-packages/openstack/config/__init__.py", line 36, in get_cloud_region
[Thu Nov 29 01:55:39.548081 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] return config.get_one(options=parsed_options, **kwargs)
[Thu Nov 29 01:55:39.548086 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/lib/python2.7/dist-packages/openstack/config/loader.py", line 1042, in get_one
[Thu Nov 29 01:55:39.548090 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] auth_plugin = loader.load_from_options(**config['auth'])
[Thu Nov 29 01:55:39.548095 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] File "/usr/lib/python2.7/dist-packages/keystoneauth1/loading/base.py", line 162, in load_from_options
[Thu Nov 29 01:55:39.548100 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] raise exceptions.MissingRequiredOptions(missing_required)
[Thu Nov 29 01:55:39.548105 2018] [wsgi:error] [pid 24:tid 140548209186560] [remote 192.168.18.195:41124] MissingRequiredOptions: Auth plugin requires parameters which were not given: auth_url
AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 172.18.0.5. Set the 'ServerName' directive globally to suppress this message

```

Because when create senlinclient, It does not provide auth_url