Move Translate snippets to test file, use new snippets.go for inclusion.

Updates snippets.go utility to Deindent and Indent by one space.

Updates to samples which are included in the docs to meet our
cdpe-snippets-rubric (show imports, show client construction, show how
to use the resulting object). I will follow-up with a PR to
java-docs-samples to remove any redundant snippets from that repo.

Why move to a test file?

We are considering moving all snippets-style samples to test files to
avoid redundant work involved with keeping snippets separate from test
files. The important thing for snippets is that they are runnable and
copy-pastable.

Ran snippets utility to include snippets in JavaDoc.

    ./utilities/snippets \
        ./google-cloud-examples/src/test/java/com/google/cloud/examples/translate/snippets/ITTranslateSnippets.java \
        ./google-cloud-clients/google-cloud-translate/src/main/java/com/google/cloud/translate/Translate.java

Author: tswast

google-cloud-clients/google-cloud-translate/src/main/java/com/google/cloud/translate/Translate.java

@@ -116,15 +116,35 @@ public static TranslateOption format(String format) {
    *
    * <p>Example of listing supported languages, localized according to
    * {@link TranslateOptions#getTargetLanguage()}:
-   * <pre> {@code
+   * <!--SNIPPET translate_list_codes-->
+   * <pre>{@code
+   * // TODO(developer): Uncomment these lines.
+   * // import com.google.cloud.translate.*;
+   * // Translate translate = TranslateOptions.getDefaultInstance().getService();
+   *
    * List<Language> languages = translate.listSupportedLanguages();
+   *
+   * for (Language language : languages) {
+   *   System.out.printf("Name: %s, Code: %s\n", language.getName(), language.getCode());
+   * }
    * }</pre>
+   * <!--SNIPPET translate_list_codes-->
    *
    * <p>Example of listing supported languages, localized according to a provided language:
-   * <pre> {@code
+   * <!--SNIPPET translate_list_language_names-->
+   * <pre>{@code
+   * // TODO(developer): Uncomment these lines.
+   * // import com.google.cloud.translate.*;
+   * // Translate translate = TranslateOptions.getDefaultInstance().getService();
+   *
    * List<Language> languages = translate.listSupportedLanguages(
-   *     LanguageListOption.targetLanguage("es"));
+   *         Translate.LanguageListOption.targetLanguage("es"));
+   *
+   * for (Language language : languages) {
+   *   System.out.printf("Name: %s, Code: %s\n", language.getName(), language.getCode());
+   * }
    * }</pre>
+   * <!--SNIPPET translate_list_language_names-->
    *
    */
   List<Language> listSupportedLanguages(LanguageListOption... options);
@@ -133,13 +153,24 @@ public static TranslateOption format(String format) {
    * Detects the language of the provided texts.
    *
    * <p>Example of detecting the language of some texts:
-   * <pre> {@code
+   * <!--SNIPPET translate_detect_language-->
+   * <pre>{@code
+   * // TODO(developer): Uncomment these lines.
+   * // import com.google.cloud.translate.*;
+   * // Translate translate = TranslateOptions.getDefaultInstance().getService();
+   *
    * List<String> texts = new LinkedList<>();
    * texts.add("Hello, World!");
    * texts.add("¡Hola Mundo!");
    * List<Detection> detections = translate.detect(texts);
-   * }</pre>
    *
+   * System.out.println("Language(s) detected:");
+   * for (Detection detection : detections) {
+   *   System.out.printf("\t%s\n", detection);
+   * }
+   * }</pre>
+   * <!--SNIPPET translate_detect_language-->
+
    * @param texts the texts for which language should be detected
    * @return a list of objects containing information on the language detection, one for each
    *     provided text, in order
@@ -150,9 +181,11 @@ public static TranslateOption format(String format) {
    * Detects the language of the provided texts.
    *
    * <p>Example of detecting the language of some texts:
-   * <pre> {@code
+   * <!--SNIPPET translate_detect_language_array-->
+   * <pre>{@code
    * List<Detection> detections = translate.detect("Hello, World!", "¡Hola Mundo!");
    * }</pre>
+   * <!--SNIPPET translate_detect_language_array-->
    *
    * @param texts the texts for which language should be detected
    * @return a list of objects containing information on the language detection, one for each
@@ -165,9 +198,11 @@ public static TranslateOption format(String format) {
    * language detection.
    *
    * <p>Example of detecting the language of a text:
-   * <pre> {@code
+   * <!--SNIPPET translate_detect_language_string-->
+   * <pre>{@code
    * Detection detection = translate.detect("Hello, World!");
    * }</pre>
+   * <!--SNIPPET translate_detect_language_string-->
    *
    */
   Detection detect(String text);
@@ -176,20 +211,26 @@ public static TranslateOption format(String format) {
    * Translates the provided texts.
    *
    * <p>Example of translating some texts:
-   * <pre> {@code
+   * <!--SNIPPET translateTexts-->
+   * <pre>{@code
    * List<String> texts = new LinkedList<>();
    * texts.add("Hello, World!");
    * texts.add("¡Hola Mundo!");
    * List<Translation> translations = translate.translate(texts);
    * }</pre>
+   * <!--SNIPPET translateTexts-->
    *
    * <p>Example of translating some texts, specifying source and target language:
-   * <pre> {@code
+   * <!--SNIPPET translateTextsWithOptions-->
+   * <pre>{@code
    * List<String> texts = new LinkedList<>();
    * texts.add("¡Hola Mundo!");
-   * List<Translation> translations = translate.translate(texts,
-   *     TranslateOption.sourceLanguage("es"), TranslateOption.targetLanguage("de"));
+   * List<Translation> translations = translate.translate(
+   *     texts,
+   *     Translate.TranslateOption.sourceLanguage("es"),
+   *     Translate.TranslateOption.targetLanguage("de"));
    * }</pre>
+   * <!--SNIPPET translateTextsWithOptions-->
    *
    * @param texts the texts to translate
    * @return a list of objects containing information on the language translation, one for each
@@ -200,18 +241,35 @@ public static TranslateOption format(String format) {
   List<Translation> translate(List<String> texts, TranslateOption... options);
 
   /**
-   * Translates the provided texts.
+   * Translates the provided text.
    *
    * <p>Example of translating a text:
-   * <pre> {@code
+   * <!--SNIPPET translate_translate_text-->
+   * <pre>{@code
+   * // TODO(developer): Uncomment these lines.
+   * // import com.google.cloud.translate.*;
+   * // Translate translate = TranslateOptions.getDefaultInstance().getService();
+   *
    * Translation translation = translate.translate("¡Hola Mundo!");
+   * System.out.printf("Translated Text:\n\t%s\n", translation.getTranslatedText());
    * }</pre>
+   * <!--SNIPPET translate_translate_text-->
+   *
+   * <p>Example of translating a text, specifying source and target language and premium model:
+   * <!--SNIPPET translate_text_with_model-->
+   * <pre>{@code
+   * Translation translation = translate.translate(
+   *     "Hola Mundo!",
+   *     Translate.TranslateOption.sourceLanguage("es"),
+   *     Translate.TranslateOption.targetLanguage("de"),
+   *     // Use "base" for standard edition, "nmt" for the premium model.
+   *     Translate.TranslateOption.model("nmt"));
    *
-   * <p>Example of translating a text, specifying source and target language:
-   * <pre> {@code
-   * Translation translation = translate.translate("¡Hola Mundo!",
-   *     TranslateOption.sourceLanguage("es"), TranslateOption.targetLanguage("de"));
+   * System.out.printf(
+   *     "TranslatedText:\nText: %s\n",
+   *     translation.getTranslatedText());
    * }</pre>
+   * <!--SNIPPET translate_text_with_model-->
    *
    * @param text the text to translate
    * @return an object containing information on the language translation