improved 404 page

Author: mauzey1

404.html

@@ -1,3 +1,8 @@
+---
+layout: default
+title: File Not Found
+---
+
 <style type="text/css">
   div.announcement {
     background: none;
@@ -17,12 +22,14 @@
 </style>
 
 <div class="hero-unit announcement">
-  <h1>404 Page</h1>
+  <h3>404: File Not Found</h3><br>
+  <p>
+    Looking for the wiki?  It has moved to <a href="https://github.com/ESGF/esgf.github.io/wiki">GitHub</a>.</br>
+  </p>
+  <p>
+    Something missing?  Report it <a href="https://github.com/ESGF/esgf.github.io/issues">here</a>.</br>
+  </p>
   <p>
-    Looking for the wiki it has moved to <a href="https://github.com/ESGF/esgf.github.io/wiki">github</a>.</br>
-    <br/>
-    Need help? <a href="http://askbot.esgf.org">Support Forum</a> <br/>
-    <br/>
-    Lost? <a href="index.html">Home Page</a>
+    <a href="{{site.url}}">Back to main page</a></br>
   </p>
 </div>