Add link to gh-pages branch

Author: cboulanger

README.md

@@ -4,10 +4,10 @@ This repository contains Qooxdoo's documentation in a versioned
 format. 
 
 Whenever a tag is pushed onto the [main framework
-repository](https://github.com/qooxdoo/qooxdoo), the content of
-the `docs` folder of that tag's source tree is deployed to the
-`gh-pages` branch of this repository in a folder named after the
-tag and published at `https://qooxdoo.org/documentation/<tag>`.
+repository](https://github.com/qooxdoo/qooxdoo), the content of the `docs`
+folder of that tag's source tree is deployed to the [`gh-pages` branch of this
+repository](https://github.com/qooxdoo/documentation/tree/gh-pages) in a folder
+named after the tag and published at `https://qooxdoo.org/documentation/<tag>`.
 
 Tags of the form `x.y.z` are shortened to `x.y` so that patch releases do
 not create separate folders. Instead, the folder of the last feature release