Remove CONF values from Token clients

To move Token clients to tempest-lib, this patch moves
CONF values from Token clients to the client setting and classes
instantiate Token clients.

Also making necessary changes in tests files.

Change-Id: Ie405ba6a71d29258e99d2f0b68afb013a9619e9b
diff --git a/tempest/tests/test_credentials.py b/tempest/tests/test_credentials.py
index 7621f6e..54a3360 100644
--- a/tempest/tests/test_credentials.py
+++ b/tempest/tests/test_credentials.py
@@ -84,7 +84,8 @@
                        self.identity_response)
 
     def _verify_credentials(self, credentials_class, creds_dict, filled=True):
-        creds = auth.get_credentials(fill_in=filled,
+        creds = auth.get_credentials(fake_identity.FAKE_AUTH_URL,
+                                     fill_in=filled,
                                      identity_version=self.identity_version,
                                      **creds_dict)
         self._check(creds, credentials_class, filled)