Adds 6 quickstart examples (#218)

* Add some simple "quickstart" samples.

* Add quickstart tests (#215)

* First draft of new tests

* Fix failing tests

* Fix comments

* Add comments.

* Update comments.

* Add another comment.

* Cleanup.

* Fix region tags.

* Fix comments.

translate/quickstart.js

@@ -0,0 +1,29 @@
+// Copyright 2015-2016, Google, Inc.
+// 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.
+
+'use strict';
+
+// [START translate_quickstart]
+// Imports and instantiates the Google Cloud client library
+// for the Google Translate API
+const translate = require('@google-cloud/translate')({
+  key: 'YOUR_API_KEY'
+});
+
+// Translates some text into Russian
+translate.translate('Hello, world!', 'ru', (err, translation, apiResponse) => {
+  if (!err) {
+    // The text was translated successfully
+  }
+});
+// [END translate_quickstart]

translate/system-test/quickstart.test.js

@@ -0,0 +1,46 @@
+// Copyright 2015-2016, Google, Inc.
+// 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.
+
+'use strict';
+
+const proxyquire = require(`proxyquire`).noPreserveCache();
+const translate = proxyquire(`@google-cloud/translate`, {})({
+  key: process.env.TRANSLATE_API_KEY
+});
+const string = `Hello, world!`;
+const targetLanguage = `ru`;
+
+describe(`translate:quickstart`, () => {
+  let translateMock, TranslateMock;
+
+  it(`should translate a string`, (done) => {
+    translateMock = {
+      translate: (_string, _targetLanguage) => {
+        assert.equal(_string, string);
+        assert.equal(_targetLanguage, targetLanguage);
+
+        translate.translate(_string, _targetLanguage, (err, translation, apiResponse) => {
+          assert.ifError(err);
+          assert.equal(translation, `Привет мир!`);
+          assert.notEqual(apiResponse, undefined);
+          done();
+        });
+      }
+    };
+    TranslateMock = sinon.stub().returns(translateMock);
+
+    proxyquire(`../quickstart`, {
+      '@google-cloud/translate': TranslateMock
+    });
+  });
+});

translate/test/quickstart.test.js

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+// Copyright 2016, Google, Inc.
+// 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.
+
+'use strict';
+
+const proxyquire = require(`proxyquire`).noCallThru();
+
+describe(`translate:quickstart`, () => {
+  let translateMock, TranslateMock;
+
+  before(() => {
+    translateMock = {
+      translate: sinon.stub().yields(null, `Привет мир!`, {})
+    };
+    TranslateMock = sinon.stub().returns(translateMock);
+  });
+
+  it(`should translate a string`, () => {
+    proxyquire(`../quickstart`, {
+      '@google-cloud/translate': TranslateMock
+    });
+
+    assert.equal(TranslateMock.calledOnce, true);
+    assert.deepEqual(TranslateMock.firstCall.args, [{ key: 'YOUR_API_KEY' }]);
+    assert.equal(translateMock.translate.calledOnce, true);
+    assert.deepEqual(translateMock.translate.firstCall.args.slice(0, -1), ['Hello, world!', 'ru']);
+  });
+});