Add metrics for the command used in the registry CLI tool

Puts the metric in <project>/tools/commands_called

It counts the use of the tool, with the following labels:
- environment
- tool (nomulus/gtech)
- command called (class name)
- success true/false
- from the shell true/false

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=212879670

java/google/registry/tools/MetricToolModule.java

@@ -0,0 +1,53 @@
+// Copyright 2018 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.api.client.googleapis.auth.oauth2.GoogleCredential;
+import com.google.api.services.monitoring.v3.Monitoring;
+import com.google.api.services.monitoring.v3.model.MonitoredResource;
+import com.google.monitoring.metrics.MetricWriter;
+import com.google.monitoring.metrics.stackdriver.StackdriverWriter;
+import dagger.Module;
+import dagger.Provides;
+import google.registry.config.CredentialModule.DefaultCredential;
+import google.registry.config.RegistryConfig.Config;
+
+/** Dagger module for metrics on the client tool. */
+@Module
+public final class MetricToolModule {
+
+  @Provides
+  static Monitoring provideMonitoring(
+      @DefaultCredential GoogleCredential credential, @Config("projectId") String projectId) {
+    return new Monitoring.Builder(
+            credential.getTransport(), credential.getJsonFactory(), credential)
+        .setApplicationName(projectId)
+        .build();
+  }
+
+  @Provides
+  static MetricWriter provideMetricWriter(
+      Monitoring monitoringClient,
+      @Config("projectId") String projectId,
+      @Config("stackdriverMaxQps") int maxQps,
+      @Config("stackdriverMaxPointsPerRequest") int maxPointsPerRequest) {
+    return new StackdriverWriter(
+        monitoringClient,
+        projectId,
+        new MonitoredResource().setType("global"),
+        maxQps,
+        maxPointsPerRequest);
+  }
+}