Add go to landing page, update StackOverflow URL (#1295)

Author: mziccard

src/site/resources/img/icon-lang-go.svg

@@ -23,38 +23,44 @@ <h1 class="logo"><img src="img/logo-full.svg" alt="Google Cloud Platform" /></h1
                 <div class="nav-current">Java</div>
                 <ul class="menu">
                     <li>
-                        <a href="http://googlecloudplatform.github.io/google-cloud-dotnet/" title=".NET docs page">
-                            <img src="img/icon-lang-dotnet.svg" alt=".NET icon" class="menu-icon" />
+                        <a href="http://googlecloudplatform.github.io/google-cloud-dotnet/" title="google-cloud-dotnet">
+                            <img src="img/icon-lang-dotnet.svg" alt="google-cloud-dotnet" class="menu-icon" />
                             .NET
                         </a>
                     </li>
                     <li>
-                        <a href="#" title="Java docs page">
-                            <img src="img/icon-lang-java-duke-white.svg" alt="Java icon" class="menu-icon" width="24" height="24" />
+                        <a href="http://googlecloudplatform.github.io/google-cloud-go/" title="google-cloud-go">
+                            <img src="img/icon-lang-go.svg" alt="google-cloud-go" class="menu-icon" />
+                            Go
+                        </a>
+                    </li>
+                    <li>
+                        <a href="#" title="google-cloud-java">
+                            <img src="img/icon-lang-java-duke-white.svg" alt="google-cloud-java" class="menu-icon" width="24" height="24" />
                             Java
                         </a>
                     </li>
                     <li>
-                        <a href="https://googlecloudplatform.github.io/google-cloud-node/" title="Node.js docs page">
-                            <img src="img/icon-lang-nodejs.svg" alt="Node.js icon" class="menu-icon" />
+                        <a href="https://googlecloudplatform.github.io/google-cloud-node/" title="google-cloud-node">
+                            <img src="img/icon-lang-nodejs.svg" alt="google-cloud-node" class="menu-icon" />
                             Node.js
                         </a>
                     </li>
                     <li>
-                        <a href="https://googlecloudplatform.github.io/google-cloud-php/" title="PHP docs page">
-                            <img src="img/icon-lang-php.svg" alt="PHP icon" class="menu-icon" />
+                        <a href="https://googlecloudplatform.github.io/google-cloud-php/" title="google-cloud-php">
+                            <img src="img/icon-lang-php.svg" alt="google-cloud-php" class="menu-icon" />
                             PHP
                         </a>
                     </li>
                     <li>
-                        <a href="https://googlecloudplatform.github.io/gcloud-python/" title="Python docs page">
-                            <img src="img/icon-lang-python.svg" alt="Python icon" class="menu-icon" />
+                        <a href="https://googlecloudplatform.github.io/google-cloud-python/" title="google-cloud-python">
+                            <img src="img/icon-lang-python.svg" alt="google-cloud-python" class="menu-icon" />
                             Python
                         </a>
                     </li>
                     <li>
-                        <a href="https://googlecloudplatform.github.io/google-cloud-ruby/" title="Ruby docs page">
-                            <img src="img/icon-lang-ruby.svg" alt="Ruby icon" class="menu-icon" />
+                        <a href="https://googlecloudplatform.github.io/google-cloud-ruby/" title="google-cloud-ruby">
+                            <img src="img/icon-lang-ruby.svg" alt="google-cloud-ruby" class="menu-icon" />
                             Ruby
                         </a>
                     </li>
@@ -103,9 +109,9 @@ <h2>Quickstart with Maven: add google-cloud to your pom.xml</h2>
                             </a>
                         </li>
                         <li>
-                            <a href="http://stackoverflow.com/questions/tagged/gcloud-java" title="google-cloud on StackOverflow" class="ext-link">
+                            <a href="https://stackoverflow.com/questions/tagged/google-cloud-platform+java" title="google-cloud on StackOverflow" class="ext-link">
                                 <img src="img/icon-link-stackoverflow.svg" alt="StackOverflow icon" />
-				StackOverflow
+                                StackOverflow
                             </a>
                         </li>
                         <li>