This patch includes several improvements:
1. Use keystoneauth1 plugin mechanism for auth plugins.
2. Implements CinderNoAuthPlugin.
3. Deletes non-working cinderclient.auth_plugin module.
4. Deprecates --bypass-url in flavor of --os-endpoint to be consistent
with keystoneauth1 plugins.
5. Deprecates in --os-auth-system in falvor of --os-auth-type to be
consistent with keystoneauth1 plugins.
Both bypass_url and os_auth_system params are not changed for client
objects to not break backward compatibility for Python API.
How to use noauth with cinderclient CLI:
OS_USER_ID=userid OS_PROJECT_ID=projectis cinder --os-auth-type noauth
--os-endpoint=http://localhost:8776/v2 list
Change-Id: I3be59a5a39235acbc3334e0a0b797081507a5c88
Closes-Bug: #1657156
60f92db704