Add entrypoint for mapped auth method

The keystone federation documentation says to use the 'mapped' method
instead of the 'saml2' method[1]. However, that entrypoint was never
added, so trying to use it resulted in keystone not being able to load
its wsgi scripts and failing. This patch adds the entrypoint so that
keystone won't explode.

[1] http://docs.openstack.org/developer/keystone/federation/federated_identity.html#configuring-federation-in-keystone

Change-Id: I6dd8c219765728ecf01b50f35c3c0da3943f13b0

keystone/tests/unit/config_files/test_auth_plugin.conf

@@ -1,4 +1,4 @@
 [auth]
-methods = external,password,token,simple_challenge_response,saml2,openid,x509
+methods = external,password,token,simple_challenge_response,saml2,openid,x509,mapped
 simple_challenge_response = keystone.tests.unit.test_auth_plugin.SimpleChallengeResponse
 

keystone/tests/unit/test_auth_plugin.py

@@ -180,7 +180,7 @@ class TestMapped(unit.TestCase):
             self.assertEqual(method_name, auth_payload['protocol'])
 
     def test_supporting_multiple_methods(self):
-        method_names = ('saml2', 'openid', 'x509')
+        method_names = ('saml2', 'openid', 'x509', 'mapped')
         self.useFixture(auth_plugins.LoadAuthPlugins(*method_names))
         for method_name in method_names:
             self._test_mapped_invocation_with_method_name(method_name)

setup.cfg

@@ -114,6 +114,9 @@ keystone.auth.totp =
 keystone.auth.x509 =
     default = keystone.auth.plugins.mapped:Mapped
 
+keystone.auth.mapped =
+    default = keystone.auth.plugins.mapped:Mapped
+
 keystone.catalog =
     sql = keystone.catalog.backends.sql:Catalog
     templated = keystone.catalog.backends.templated:Catalog