Update list of available versions.

Author: daobrien

index.html

@@ -48,18 +48,16 @@
       </p>
 
       <h3>
-      <a href="https://stylepedia.net/style/4.2" target="_blank" title="The Red&nbsp;Hat Technical Writing Style Guide">
-        <img class="social" src="font/fontawesome/svgs/brands/readme.svg" alt="Style Guide" width="40em" /> Red&nbsp;Hat Technical Writing Style Guide v4.2</a>
+      <a href="https://stylepedia.net/style/5.0" target="_blank" title="The Red&nbsp;Hat Technical Writing Style Guide">
+        <img class="social" src="font/fontawesome/svgs/brands/readme.svg" alt="Style Guide" width="40em" /> Red&nbsp;Hat Technical Writing Style Guide v5.0</a>
     </h3>
 
       <h3>
-      <a href="https://stylepedia.net/style/5.0" target="_blank" title="The Red&nbsp;Hat Technical Writing Style Guide">
-        <img class="social" src="font/fontawesome/svgs/brands/readme.svg" alt="Style Guide" width="40em" /> Red&nbsp;Hat Technical Writing Style Guide v5.0</a>
+      <a href="https://stylepedia.net/style/5.1" target="_blank" title="The Red&nbsp;Hat Technical Writing Style Guide">
+        <img class="social" src="font/fontawesome/svgs/brands/readme.svg" alt="Style Guide" width="40em" /> Red&nbsp;Hat Technical Writing Style Guide v5.1</a>
     </h3>
 
-    <!--<h3>
-      <a href="http://stylepedia.net/docbook/3.1" title="DocBook XML Guide v3.1">
-    <img class="social" src="font/fontawesome/svgs/solid/code.svg" alt="XML Guide" width="40em" /> RHT DocBook XML Guide v3.1</a>-->
+
     </h3>
 
       <h3>