Fix broken link to docs

Author: beetlehope

README.md

@@ -2,7 +2,7 @@ Sinatra Website / Documentation
 ===============================
 
 This repo contains the Sinatra website and documentation sources published
-at [http://sinatra.github.com/](http://sinatra.github.com/).
+at [http://sinatra.github.com/](http://sinatra.github.io/).
 
 Working Locally
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