Convert AppEngineConnection to use HttpTransport

Make AppEngineConnection use HttpTransport through HttpRequestFactory and
create factory factories for localhost and HTTPOverRPC.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=143680257

java/google/registry/tools/AppEngineConnectionFlagsModule.java

@@ -0,0 +1,36 @@
+// Copyright 2016 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.tools;
+
+import com.google.common.net.HostAndPort;
+import dagger.Module;
+import dagger.Provides;
+
+/**
+ * Dagger module to provide communication flags for talking to App Engine.
+ */
+@Module
+public final class AppEngineConnectionFlagsModule {
+  private final AppEngineConnectionFlags flags;
+
+  AppEngineConnectionFlagsModule(AppEngineConnectionFlags flags) {
+    this.flags = flags;
+  }
+
+  @Provides
+  HostAndPort provideServer() {
+    return flags.getServer();
+  }
+}