Change @Auth to an AutoValue, and created a set of predefined Auths

We want to be safer and more explicit about the authentication needed by the many actions that exist.

As such, we make the 'auth' parameter required in @Action (so it's always clear who can run a specific action) and we replace the @Auth with an enum so that only pre-approved configurations that are aptly named and documented can be used.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162210306

javatests/google/registry/request/auth/AuthTest.java

@@ -0,0 +1,31 @@
+// Copyright 2017 The Nomulus Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.request.auth;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link Auth}. */
+@RunWith(JUnit4.class)
+public final class AuthTest {
+
+  @Test
+  public void testAuthValues_validConfig() throws Exception {
+    for (Auth auth : Auth.values()) {
+      RequestAuthenticator.checkAuthConfig(auth.authSettings());
+    }
+  }
+}