Add deprecation message to LTv2 constructors

Author: mediumTaj

src/IBM.WatsonDeveloperCloud.LanguageTranslator.v2/LanguageTranslatorService.cs

@@ -34,12 +34,14 @@ public partial class LanguageTranslatorService : WatsonService, ILanguageTransla
         const string URL = "https://gateway.watsonplatform.net/language-translator/api";
         public LanguageTranslatorService() : base(SERVICE_NAME, URL)
         {
+            Console.WriteLine("Language Translator v3 is now available. The v2 Language Translator API will no longer be available after July 31, 2018. To take advantage of the latest service enhancements, migrate to the v3 API. View the [Migrating to Language Translator v3](https://console.bluemix.net/docs/services/language-translator/migrating.html) page for more information.");
             if(!string.IsNullOrEmpty(this.Endpoint))
                 this.Endpoint = URL;
         }
 
         public LanguageTranslatorService(string userName, string password) : this()
         {
+            Console.WriteLine("Language Translator v3 is now available. The v2 Language Translator API will no longer be available after July 31, 2018. To take advantage of the latest service enhancements, migrate to the v3 API. View the [Migrating to Language Translator v3](https://console.bluemix.net/docs/services/language-translator/migrating.html) page for more information.");
             if (string.IsNullOrEmpty(userName))
                 throw new ArgumentNullException(nameof(userName));
 
@@ -51,6 +53,7 @@ public LanguageTranslatorService(string userName, string password) : this()
 
         public LanguageTranslatorService(TokenOptions options) : this()
         {
+            Console.WriteLine("Language Translator v3 is now available. The v2 Language Translator API will no longer be available after July 31, 2018. To take advantage of the latest service enhancements, migrate to the v3 API. View the [Migrating to Language Translator v3](https://console.bluemix.net/docs/services/language-translator/migrating.html) page for more information.");
             if (string.IsNullOrEmpty(options.IamApiKey) && string.IsNullOrEmpty(options.IamAccessToken))
                 throw new ArgumentNullException(nameof(options.IamAccessToken) + ", " + nameof(options.IamApiKey));
             if (!string.IsNullOrEmpty(options.ServiceUrl))
@@ -67,6 +70,7 @@ public LanguageTranslatorService(TokenOptions options) : this()
 
         public LanguageTranslatorService(IClient httpClient) : this()
         {
+            Console.WriteLine("Language Translator v3 is now available. The v2 Language Translator API will no longer be available after July 31, 2018. To take advantage of the latest service enhancements, migrate to the v3 API. View the [Migrating to Language Translator v3](https://console.bluemix.net/docs/services/language-translator/migrating.html) page for more information.");
             if (httpClient == null)
                 throw new ArgumentNullException(nameof(httpClient));