added a RSS validator banner to the about page

content/pages/about.en.md

@@ -30,4 +30,4 @@ In addition to the above web services *varia* hosts a server for the federated c
 ## RSS
 Subscribe to our RSS feeds, available in [Dutch](http://varia.zone/feeds/all-nl.rss.xml) and [English](http://varia.zone/feeds/all-en.rss.xml). 
 
-<a href="https://validator.w3.org/feed/check.cgi?url=http%3A//varia.zone/feeds/all-nl.rss.xml"><img src="valid-rss-rogers.png" alt="[Valid RSS]" title="Validate my RSS feed" /></a>
+<a href="https://validator.w3.org/feed/check.cgi?url=http%3A//varia.zone/feeds/all-nl.rss.xml"><img src="/images/valid-rss-rogers.png" alt="[Valid RSS]" title="Validate my RSS feed" /></a>