Actionize the EPP endpoints.

This introduces Actions and Dagger up until FlowRunner. The changes
to the servlets are relatively simple, but the required changes to
the tests, as well as to auxillary EPP endpoints (such as the http
check api and the load test servlet) were vast. I've added some
comments in critique to make the review easier that don't really
make sense as in-code comments for the future.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=124593546

javatests/google/registry/testing/ShardableTestCase.java

@@ -0,0 +1,34 @@
+// Copyright 2016 The Domain Registry 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.testing;
+
+import org.junit.Test;
+
+/**
+ * Test case with 3 empty methods.
+ *
+ * The sharding test runner fails if it produces an empty shard, and we shard 4 ways. This makes
+ * sure that we never produces empty shards.
+ */
+public abstract class ShardableTestCase {
+  @Test
+  public void testNothing1() {}
+
+  @Test
+  public void testNothing2() {}
+
+  @Test
+  public void testNothing3() {}
+}