Center text.

docs/index.html

@@ -23,7 +23,7 @@ slug: home
 </main>
 
 <section class="notice-previous">
-  <div class="container">
+  <div class="container text-center">
     <a href="http://select2.github.io/select2/">Looking for the Select2 3.5.2 docs?</a>
     We have moved them to a new location
     <a href="announcements-4.0.html">while we push forward with Select2 4.0</a>.