center align alert box text

Signed-off-by: Eric Poirier <eric.poirier@eclipse-foundation.org>

content/en_index.php

diff --git a/content/en_index.php b/content/en_index.php
index 1ecb290..e7065b4 100755
--- a/content/en_index.php
+++ b/content/en_index.php
@@ -15,7 +15,7 @@
 $oxygen_content_items = json_decode(file_get_contents($oxygen_content_json), TRUE);
 
 ?>
-<div style="background-color:#6d6d6d;padding-top:20px;">
+<div style="background-color:#6d6d6d;padding-top:20px;text-align:center;">
   <div class="container">
     <div class="alert alert-danger" role="alert">
       <a href="https://projects.eclipse.org/releases/oxygen">Oxygen</a> is